diff --git a/action.yml b/action.yml
index 83c0e249..b4562c8c 100644
--- a/action.yml
+++ b/action.yml
@@ -36,6 +36,17 @@ inputs:
     description: 'Item Value, Only required for batch-put operation'
     required: false
 
+  #Update Operation
+  updateExpression:
+    description: 'Attribute variables, Only required for update operation'
+    required: false
+  expressionAttributeValues:
+    description: 'Attribute values to be updated, Only required for update operation'
+    required: false
+  expressionAttributeFiles:
+    description: 'Attribute files to be updated, Only required for update operation'
+    required: false
+
 outputs:
   item:
     description: 'JSON-serialized Item'
diff --git a/dist/index.js b/dist/index.js
index 98fdc4fe..be688768 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -11,7 +11,7 @@ const processor = new processor_1.Processor();
         operation: (_a = core.getInput("operation")) === null || _a === void 0 ? void 0 : _a.toLowerCase(),
         region: core.getInput("region"),
         table: core.getInput("table"),
-        // Get / Delete Operation
+        // Get / Delete / Update Operation
         key: helpers_1.forgivingJSONParse(core.getInput("key")),
         consistent: helpers_1.forgivingJSONParse(core.getInput("consistent")),
         // Put Operation
@@ -20,6 +20,10 @@ const processor = new processor_1.Processor();
         // BatchPut Operation
         items: helpers_1.forgivingJSONParse(core.getInput("items")),
         files: core.getInput("files"),
+        // Update Operation
+        updateExpression: core.getInput("updateExpression"),
+        expressionAttributeValues: core.getInput("expressionAttributeValues"),
+        expressionAttributeFiles: core.getInput("expressionAttributeFiles")
     };
     const output = await processor.process(input);
     if (output) {
diff --git a/dist/operations/batch-put.js b/dist/operations/batch-put.js
index 088c4318..c9c9f993 100644
--- a/dist/operations/batch-put.js
+++ b/dist/operations/batch-put.js
@@ -2,7 +2,7 @@
 Object.defineProperty(exports, "__esModule", { value: true });
 exports.BatchPutOperation = void 0;
 const glob = require("@actions/glob");
-const Joi = require("@hapi/joi");
+const Joi = require("joi");
 const fs_1 = require("fs");
 const helpers_1 = require("../helpers");
 const BaseInputSchema = Joi.object({
diff --git a/dist/operations/delete.js b/dist/operations/delete.js
index de9ad447..09d3b9ae 100644
--- a/dist/operations/delete.js
+++ b/dist/operations/delete.js
@@ -1,7 +1,7 @@
 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
 exports.DeleteOperation = void 0;
-const Joi = require("@hapi/joi");
+const Joi = require("joi");
 const helpers_1 = require("../helpers");
 const InputSchema = Joi.object({
     operation: Joi.string().lowercase().valid("delete").required(),
diff --git a/dist/operations/get.js b/dist/operations/get.js
index e176d07d..c544cd55 100644
--- a/dist/operations/get.js
+++ b/dist/operations/get.js
@@ -1,7 +1,7 @@
 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
 exports.GetOperation = void 0;
-const Joi = require("@hapi/joi");
+const Joi = require("joi");
 const helpers_1 = require("../helpers");
 const InputSchema = Joi.object({
     operation: Joi.string().lowercase().valid("get").required(),
diff --git a/dist/operations/index.js b/dist/operations/index.js
index 2810ef89..af282a0a 100644
--- a/dist/operations/index.js
+++ b/dist/operations/index.js
@@ -7,7 +7,7 @@ var __createBinding = (this && this.__createBinding) || (Object.create ? (functi
     o[k2] = m[k];
 }));
 var __exportStar = (this && this.__exportStar) || function(m, exports) {
-    for (var p in m) if (p !== "default" && !exports.hasOwnProperty(p)) __createBinding(exports, m, p);
+    for (var p in m) if (p !== "default" && !Object.prototype.hasOwnProperty.call(exports, p)) __createBinding(exports, m, p);
 };
 Object.defineProperty(exports, "__esModule", { value: true });
 __exportStar(require("./base"), exports);
@@ -15,3 +15,4 @@ __exportStar(require("./batch-put"), exports);
 __exportStar(require("./delete"), exports);
 __exportStar(require("./get"), exports);
 __exportStar(require("./put"), exports);
+__exportStar(require("./update"), exports);
diff --git a/dist/operations/put.js b/dist/operations/put.js
index 6c7cabd2..15f2fa92 100644
--- a/dist/operations/put.js
+++ b/dist/operations/put.js
@@ -1,7 +1,7 @@
 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
 exports.PutOperation = void 0;
-const Joi = require("@hapi/joi");
+const Joi = require("joi");
 const fs_1 = require("fs");
 const helpers_1 = require("../helpers");
 const BaseInputSchema = Joi.object({
diff --git a/dist/operations/update.js b/dist/operations/update.js
new file mode 100644
index 00000000..ddc86cfe
--- /dev/null
+++ b/dist/operations/update.js
@@ -0,0 +1,96 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.UpdateOperation = void 0;
+const Joi = require("joi");
+const fs_1 = require("fs");
+const helpers_1 = require("../helpers");
+const BaseInputSchema = Joi.object({
+    operation: Joi.string().lowercase().valid("update").required(),
+    region: Joi.string().lowercase().required(),
+    table: Joi.string().required(),
+    updateExpression: Joi.string().required()
+});
+const InputSchema = Joi.alternatives([
+    BaseInputSchema.append({
+        expressionAttributeValues: Joi.string().required(),
+        key: Joi.object().required(),
+    }),
+    BaseInputSchema.append({
+        expressionAttributeFiles: Joi.string().required(),
+        key: Joi.object().required(),
+    }),
+]).required();
+class UpdateOperation {
+    constructor() {
+        this.name = "update";
+    }
+    async validate(input) {
+        const validationResult = InputSchema.validate(input, {
+            stripUnknown: true,
+        });
+        if (validationResult.error) {
+            throw validationResult.error;
+        }
+        return validationResult.value;
+    }
+    async execute(input) {
+        const ddb = helpers_1.createClient(input.region);
+        let updateExp = ``;
+        let attValues = {};
+        const expressions = await this.buildExpression(updateExp, input);
+        const attributes = await this.buildAttributes(expressions, attValues, input);
+        console.log(expressions);
+        console.log(attributes);
+        await ddb.update({
+            TableName: input.table,
+            Key: input.key,
+            UpdateExpression: expressions,
+            ExpressionAttributeValues: attributes
+        }).promise();
+    }
+    async read(path) {
+        const content = await fs_1.promises.readFile(path, { encoding: "utf8" });
+        return JSON.parse(content);
+    }
+    async buildExpression(updateExp, input) {
+        const updateExpressions = input.updateExpression.split(',');
+        for (let i = 0; i < updateExpressions.length; i++) {
+            if (i === 0 && updateExpressions.length > 1) {
+                updateExp = `set ${updateExpressions[i]} = :${updateExpressions[i]},`;
+            }
+            else if (i === 0 && updateExpressions.length === 1) {
+                updateExp = `set ${updateExpressions[i]} = :${updateExpressions[i]}`;
+            }
+            else if (i === updateExpressions.length - 1) {
+                updateExp += ` ${updateExpressions[i]} = :${updateExpressions[i]}`;
+            }
+            else {
+                updateExp += ` ${updateExpressions[i]} = :${updateExpressions[i]},`;
+            }
+        }
+        return updateExp;
+    }
+    async buildAttributes(updateExp, attValues, input) {
+        const updateExpressions = updateExp.split(',');
+        if (input.expressionAttributeValues) {
+            const expAttValues = input.expressionAttributeValues.split(', ');
+            const keyValues = [];
+            for (let i = 0; i < updateExpressions.length; i++) {
+                updateExpressions[i] = updateExpressions[i].substring(updateExpressions[i].indexOf(":"));
+                keyValues[i] = [updateExpressions[i], expAttValues[i]];
+            }
+            attValues = Object.fromEntries(keyValues);
+        }
+        else if (input.expressionAttributeFiles) {
+            const expAttValues = input.expressionAttributeFiles.split(',');
+            const keyValues = [];
+            for (let i = 0; i < updateExpressions.length; i++) {
+                updateExpressions[i] = updateExpressions[i].substring(updateExpressions[i].indexOf(":"));
+                keyValues[i] = [updateExpressions[i], await this.read(expAttValues[i])];
+            }
+            attValues = Object.fromEntries(keyValues);
+        }
+        return attValues;
+    }
+}
+exports.UpdateOperation = UpdateOperation;
diff --git a/dist/processor.js b/dist/processor.js
index f8ec2a32..61f950fd 100644
--- a/dist/processor.js
+++ b/dist/processor.js
@@ -9,6 +9,7 @@ class Processor {
             new operations_1.DeleteOperation(),
             new operations_1.GetOperation(),
             new operations_1.PutOperation(),
+            new operations_1.UpdateOperation()
         ];
     }
     async process(input) {
diff --git a/package-lock.json b/package-lock.json
index 0d88e5b0..f7c2c076 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -222,6 +222,20 @@
         "@commitlint/top-level": "^11.0.0",
         "fs-extra": "^9.0.0",
         "git-raw-commits": "^2.0.0"
+      },
+      "dependencies": {
+        "fs-extra": {
+          "version": "9.1.0",
+          "resolved": "https://registry.npmjs.org/fs-extra/-/fs-extra-9.1.0.tgz",
+          "integrity": "sha512-hcg3ZmepS30/7BSFqRvoo3DOMQu7IjqxO5nCDt+zM9XWjb33Wg7ziNT+Qvqbuc3+gWpzO02JubVyk2G4Zvo1OQ==",
+          "dev": true,
+          "requires": {
+            "at-least-node": "^1.0.0",
+            "graceful-fs": "^4.2.0",
+            "jsonfile": "^6.0.1",
+            "universalify": "^2.0.0"
+          }
+        }
       }
     },
     "@commitlint/resolve-extends": {
@@ -308,40 +322,10 @@
       "integrity": "sha512-VoNqai1vR5anRF5Tuh/+SWDFk7xi7oMwHrHrbm1BprYXjB2RJsWLhUrStMssDxEl5lW/z3EUdg8RvH/IUBccSQ==",
       "dev": true
     },
-    "@hapi/address": {
-      "version": "4.1.0",
-      "resolved": "https://registry.npmjs.org/@hapi/address/-/address-4.1.0.tgz",
-      "integrity": "sha512-SkszZf13HVgGmChdHo/PxchnSaCJ6cetVqLzyciudzZRT0jcOouIF/Q93mgjw8cce+D+4F4C1Z/WrfFN+O3VHQ==",
-      "requires": {
-        "@hapi/hoek": "^9.0.0"
-      }
-    },
-    "@hapi/formula": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/@hapi/formula/-/formula-2.0.0.tgz",
-      "integrity": "sha512-V87P8fv7PI0LH7LiVi8Lkf3x+KCO7pQozXRssAHNXXL9L1K+uyu4XypLXwxqVDKgyQai6qj3/KteNlrqDx4W5A=="
-    },
     "@hapi/hoek": {
-      "version": "9.1.1",
-      "resolved": "https://registry.npmjs.org/@hapi/hoek/-/hoek-9.1.1.tgz",
-      "integrity": "sha512-CAEbWH7OIur6jEOzaai83jq3FmKmv4PmX1JYfs9IrYcGEVI/lyL1EXJGCj7eFVJ0bg5QR8LMxBlEtA+xKiLpFw=="
-    },
-    "@hapi/joi": {
-      "version": "17.1.1",
-      "resolved": "https://registry.npmjs.org/@hapi/joi/-/joi-17.1.1.tgz",
-      "integrity": "sha512-p4DKeZAoeZW4g3u7ZeRo+vCDuSDgSvtsB/NpfjXEHTUjSeINAi/RrVOWiVQ1isaoLzMvFEhe8n5065mQq1AdQg==",
-      "requires": {
-        "@hapi/address": "^4.0.1",
-        "@hapi/formula": "^2.0.0",
-        "@hapi/hoek": "^9.0.0",
-        "@hapi/pinpoint": "^2.0.0",
-        "@hapi/topo": "^5.0.0"
-      }
-    },
-    "@hapi/pinpoint": {
-      "version": "2.0.0",
-      "resolved": "https://registry.npmjs.org/@hapi/pinpoint/-/pinpoint-2.0.0.tgz",
-      "integrity": "sha512-vzXR5MY7n4XeIvLpfl3HtE3coZYO4raKXW766R6DZw/6aLqR26iuZ109K7a0NtF2Db0jxqh7xz2AxkUwpUFybw=="
+      "version": "9.2.0",
+      "resolved": "https://registry.npmjs.org/@hapi/hoek/-/hoek-9.2.0.tgz",
+      "integrity": "sha512-sqKVVVOe5ivCaXDWivIJYVSaEgdQK9ul7a4Kity5Iw7u9+wBAPbX1RMSnLLmp7O4Vzj0WOWwMAJsTL00xwaNug=="
     },
     "@hapi/topo": {
       "version": "5.0.0",
@@ -527,6 +511,20 @@
         "aggregate-error": "^3.0.0",
         "fs-extra": "^9.0.0",
         "lodash": "^4.17.4"
+      },
+      "dependencies": {
+        "fs-extra": {
+          "version": "9.1.0",
+          "resolved": "https://registry.npmjs.org/fs-extra/-/fs-extra-9.1.0.tgz",
+          "integrity": "sha512-hcg3ZmepS30/7BSFqRvoo3DOMQu7IjqxO5nCDt+zM9XWjb33Wg7ziNT+Qvqbuc3+gWpzO02JubVyk2G4Zvo1OQ==",
+          "dev": true,
+          "requires": {
+            "at-least-node": "^1.0.0",
+            "graceful-fs": "^4.2.0",
+            "jsonfile": "^6.0.1",
+            "universalify": "^2.0.0"
+          }
+        }
       }
     },
     "@semantic-release/commit-analyzer": {
@@ -858,6 +856,24 @@
         }
       }
     },
+    "@sideway/address": {
+      "version": "4.1.2",
+      "resolved": "https://registry.npmjs.org/@sideway/address/-/address-4.1.2.tgz",
+      "integrity": "sha512-idTz8ibqWFrPU8kMirL0CoPH/A29XOzzAzpyN3zQ4kAWnzmNfFmRaoMNN6VI8ske5M73HZyhIaW4OuSFIdM4oA==",
+      "requires": {
+        "@hapi/hoek": "^9.0.0"
+      }
+    },
+    "@sideway/formula": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/@sideway/formula/-/formula-3.0.0.tgz",
+      "integrity": "sha512-vHe7wZ4NOXVfkoRb8T5otiENVlT7a3IAiw7H5M2+GO+9CDgcVUUsX1zalAztCmwyOr2RUTGJdgB+ZvSVqmdHmg=="
+    },
+    "@sideway/pinpoint": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/@sideway/pinpoint/-/pinpoint-2.0.0.tgz",
+      "integrity": "sha512-RNiOoTPkptFtSVzQevY/yWtZwf/RxyVnPy/OcA9HBM3MlGDnBEYL5B41H0MTn0Uec8Hi+2qUtTfG2WWZBmMejQ=="
+    },
     "@tootallnate/once": {
       "version": "1.1.2",
       "resolved": "https://registry.npmjs.org/@tootallnate/once/-/once-1.1.2.tgz",
@@ -870,6 +886,15 @@
       "integrity": "sha512-rS27+EkB/RE1Iz3u0XtVL5q36MGDWbgYe7zWiodyKNUnthxY0rukK5V36eiUCtCisB7NN8zKYH6DO2M37qxFEQ==",
       "dev": true
     },
+    "@types/fs-extra": {
+      "version": "9.0.11",
+      "resolved": "https://registry.npmjs.org/@types/fs-extra/-/fs-extra-9.0.11.tgz",
+      "integrity": "sha512-mZsifGG4QeQ7hlkhO56u7zt/ycBgGxSVsFI/6lGTU34VtwkiqrrSDgw0+ygs8kFGWcXnFQWMrzF2h7TtDFNixA==",
+      "dev": true,
+      "requires": {
+        "@types/node": "*"
+      }
+    },
     "@types/hapi__joi": {
       "version": "17.1.6",
       "resolved": "https://registry.npmjs.org/@types/hapi__joi/-/hapi__joi-17.1.6.tgz",
@@ -2135,12 +2160,10 @@
       }
     },
     "fs-extra": {
-      "version": "9.1.0",
-      "resolved": "https://registry.npmjs.org/fs-extra/-/fs-extra-9.1.0.tgz",
-      "integrity": "sha512-hcg3ZmepS30/7BSFqRvoo3DOMQu7IjqxO5nCDt+zM9XWjb33Wg7ziNT+Qvqbuc3+gWpzO02JubVyk2G4Zvo1OQ==",
-      "dev": true,
+      "version": "10.0.0",
+      "resolved": "https://registry.npmjs.org/fs-extra/-/fs-extra-10.0.0.tgz",
+      "integrity": "sha512-C5owb14u9eJwizKGdchcDUQeFtlSHHthBk8pbX9Vc1PFZrLombudjDnNns88aYslCyF6IY5SUw3Roz6xShcEIQ==",
       "requires": {
-        "at-least-node": "^1.0.0",
         "graceful-fs": "^4.2.0",
         "jsonfile": "^6.0.1",
         "universalify": "^2.0.0"
@@ -2343,8 +2366,7 @@
     "graceful-fs": {
       "version": "4.2.6",
       "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.6.tgz",
-      "integrity": "sha512-nTnJ528pbqxYanhpDYsi4Rd8MAeaBA67+RZ10CM1m3bTAVFEDcd5AuA4a6W5YkGZ1iNXHzZz8T6TBKLeBuNriQ==",
-      "dev": true
+      "integrity": "sha512-nTnJ528pbqxYanhpDYsi4Rd8MAeaBA67+RZ10CM1m3bTAVFEDcd5AuA4a6W5YkGZ1iNXHzZz8T6TBKLeBuNriQ=="
     },
     "growl": {
       "version": "1.10.5",
@@ -2812,6 +2834,18 @@
       "resolved": "https://registry.npmjs.org/jmespath/-/jmespath-0.15.0.tgz",
       "integrity": "sha1-o/Iiqarp+Wb10nx5ZRDigJF2Qhc="
     },
+    "joi": {
+      "version": "17.4.0",
+      "resolved": "https://registry.npmjs.org/joi/-/joi-17.4.0.tgz",
+      "integrity": "sha512-F4WiW2xaV6wc1jxete70Rw4V/VuMd6IN+a5ilZsxG4uYtUXWu2kq9W5P2dz30e7Gmw8RCbY/u/uk+dMPma9tAg==",
+      "requires": {
+        "@hapi/hoek": "^9.0.0",
+        "@hapi/topo": "^5.0.0",
+        "@sideway/address": "^4.1.0",
+        "@sideway/formula": "^3.0.0",
+        "@sideway/pinpoint": "^2.0.0"
+      }
+    },
     "js-tokens": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/js-tokens/-/js-tokens-4.0.0.tgz",
@@ -2849,7 +2883,6 @@
       "version": "6.1.0",
       "resolved": "https://registry.npmjs.org/jsonfile/-/jsonfile-6.1.0.tgz",
       "integrity": "sha512-5dgndWOriYSm5cnYaJNhalLNDKOqFwyDB/rr1E9ZsGciGvKPs8R2xYGCacuf3z6K1YKDz182fd+fY3cn3pMqXQ==",
-      "dev": true,
       "requires": {
         "graceful-fs": "^4.1.6",
         "universalify": "^2.0.0"
@@ -6808,8 +6841,7 @@
     "universalify": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/universalify/-/universalify-2.0.0.tgz",
-      "integrity": "sha512-hAZsKq7Yy11Zu1DE0OzWjw7nnLZmJZYTDZZyEFHZdUhV8FkH5MCfoU1XMaxXovpyW5nq5scPqq0ZDP9Zyl04oQ==",
-      "dev": true
+      "integrity": "sha512-hAZsKq7Yy11Zu1DE0OzWjw7nnLZmJZYTDZZyEFHZdUhV8FkH5MCfoU1XMaxXovpyW5nq5scPqq0ZDP9Zyl04oQ=="
     },
     "url": {
       "version": "0.10.3",
diff --git a/package.json b/package.json
index fa95b3d4..a41cd444 100644
--- a/package.json
+++ b/package.json
@@ -33,6 +33,7 @@
     "@semantic-release/git": "9.0.0",
     "@semantic-release/release-notes-generator": "9.0.3",
     "@types/chai": "4.2.18",
+    "@types/fs-extra": "^9.0.11",
     "@types/hapi__joi": "17.1.6",
     "@types/joi": "14.3.4",
     "@types/mocha": "8.2.2",
@@ -49,8 +50,9 @@
   "dependencies": {
     "@actions/core": "^1.2.6",
     "@actions/glob": "^0.2.0",
-    "@hapi/joi": "^17.1.1",
-    "aws-sdk": "^2.703.0"
+    "aws-sdk": "^2.703.0",
+    "fs-extra": "^10.0.0",
+    "joi": "^17.4.0"
   },
   "config": {
     "commitizen": {
diff --git a/src/index.ts b/src/index.ts
index 4478b85c..c5688405 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -12,7 +12,7 @@ const processor = new Processor();
     region: core.getInput("region"),
     table: core.getInput("table"),
 
-    // Get / Delete Operation
+    // Get / Delete / Update Operation
     key: forgivingJSONParse(core.getInput("key")),
     consistent: forgivingJSONParse(core.getInput("consistent")),
 
@@ -23,6 +23,11 @@ const processor = new Processor();
     // BatchPut Operation
     items: forgivingJSONParse(core.getInput("items")),
     files: core.getInput("files"),
+
+    // Update Operation
+    updateExpression: core.getInput("updateExpression"),
+    expressionAttributeValues: core.getInput("expressionAttributeValues"),
+    expressionAttributeFiles: core.getInput("expressionAttributeFiles")
   };
 
   const output = await processor.process(input);
diff --git a/src/operations/batch-put.ts b/src/operations/batch-put.ts
index 217bac4d..557e086b 100644
--- a/src/operations/batch-put.ts
+++ b/src/operations/batch-put.ts
@@ -1,5 +1,5 @@
 import * as glob from "@actions/glob";
-import * as Joi from "@hapi/joi";
+import * as Joi from "joi";
 import { promises as fs } from "fs";
 import { createClient } from "../helpers";
 import { Operation } from "./base";
diff --git a/src/operations/delete.ts b/src/operations/delete.ts
index fb162f6c..7258a2bd 100644
--- a/src/operations/delete.ts
+++ b/src/operations/delete.ts
@@ -1,4 +1,4 @@
-import * as Joi from "@hapi/joi";
+import * as Joi from "joi";
 import { createClient } from "../helpers";
 import { Operation } from "./base";
 
diff --git a/src/operations/get.ts b/src/operations/get.ts
index eec96bf0..ede7185d 100644
--- a/src/operations/get.ts
+++ b/src/operations/get.ts
@@ -1,4 +1,4 @@
-import * as Joi from "@hapi/joi";
+import * as Joi from "joi";
 import { createClient } from "../helpers";
 import { Operation } from "./base";
 
diff --git a/src/operations/index.ts b/src/operations/index.ts
index 7e9d7930..fb92659d 100644
--- a/src/operations/index.ts
+++ b/src/operations/index.ts
@@ -4,3 +4,4 @@ export * from "./batch-put";
 export * from "./delete";
 export * from "./get";
 export * from "./put";
+export * from "./update";
diff --git a/src/operations/put.ts b/src/operations/put.ts
index d044ebc3..3dbd2bbc 100644
--- a/src/operations/put.ts
+++ b/src/operations/put.ts
@@ -1,4 +1,4 @@
-import * as Joi from "@hapi/joi";
+import * as Joi from "joi";
 import { promises as fs } from "fs";
 import { createClient } from "../helpers";
 import { Operation } from "./base";
diff --git a/src/operations/update.ts b/src/operations/update.ts
new file mode 100644
index 00000000..56aefe91
--- /dev/null
+++ b/src/operations/update.ts
@@ -0,0 +1,127 @@
+import * as Joi from "joi";
+import { promises as fs } from "fs";
+import { createClient } from "../helpers";
+import { Operation } from "./base"; 
+
+const BaseInputSchema = Joi.object({
+  operation: Joi.string().lowercase().valid("update").required(),
+  region: Joi.string().lowercase().required(),
+  table: Joi.string().required(),
+  updateExpression: Joi.string().required()
+});
+
+const InputSchema = Joi.alternatives([
+  BaseInputSchema.append({
+    expressionAttributeValues: Joi.string().required(),
+    key: Joi.object().required(),
+  }),
+  BaseInputSchema.append({
+    expressionAttributeFiles: Joi.string().required(),
+    key: Joi.object().required(),
+  }),
+]).required();
+
+export type UpdateOperationInput = {
+  operation: "update";
+  region: string;
+  table: string;
+  updateExpression: string;
+} & ({
+  expressionAttributeValues: string;
+  expressionAttributeFiles?: never;
+  key: { [key: string]: any };
+} | {
+  expressionAttributeValues?: never;
+  expressionAttributeFiles: string;
+  key: { [key: string]: any };
+});
+
+export class UpdateOperation implements Operation<UpdateOperationInput> {
+  public readonly name = "update";
+
+  public async validate(input: unknown): Promise<UpdateOperationInput> {
+    const validationResult = InputSchema.validate(input, {
+      stripUnknown: true,
+    });
+    if (validationResult.error) {
+      throw validationResult.error;
+    }
+
+    return validationResult.value as UpdateOperationInput;
+  }
+
+  public async execute(input: UpdateOperationInput) {
+    const ddb = createClient(input.region);
+    let updateExp = ``;
+    let attValues = {};
+
+    const expressions = await this.buildExpression(updateExp, input);
+    const attributes = await this.buildAttributes(expressions, attValues, input);
+
+    console.log(expressions);
+    console.log(attributes);
+
+    await ddb.update({
+      TableName: input.table,
+      Key: input.key,
+      UpdateExpression: expressions,
+      ExpressionAttributeValues: attributes
+    }).promise();
+  }
+
+  private async read(path: string) {
+    const content = await fs.readFile(path, { encoding: "utf8" });
+
+    return JSON.parse(content);
+  }
+
+  private async buildExpression(updateExp: string, input: UpdateOperationInput) {
+    const updateExpressions = input.updateExpression.split(',');
+
+    for(let i=0; i<updateExpressions.length; i++) {
+      if(i===0 && updateExpressions.length > 1) {
+        updateExp = `set ${updateExpressions[i]} = :${updateExpressions[i]},`;
+      }
+      else if(i===0 && updateExpressions.length === 1) {
+        updateExp = `set ${updateExpressions[i]} = :${updateExpressions[i]}`;
+      }
+      else if(i===updateExpressions.length-1) {
+        updateExp += ` ${updateExpressions[i]} = :${updateExpressions[i]}`;
+      }
+      else {
+        updateExp += ` ${updateExpressions[i]} = :${updateExpressions[i]},`;
+      }
+    }
+
+    return updateExp;
+  }
+
+  private async buildAttributes(updateExp: string, attValues: {}, input: UpdateOperationInput) {
+    const updateExpressions = updateExp.split(',');
+
+    if(input.expressionAttributeValues) {
+      const expAttValues = input.expressionAttributeValues.split(', ');
+      const keyValues = [];
+
+      for(let i=0; i<updateExpressions.length; i++) {
+        updateExpressions[i] = updateExpressions[i].substring(updateExpressions[i].indexOf(":"));
+        keyValues[i] = [updateExpressions[i], expAttValues[i]];
+      }
+
+      attValues = Object.fromEntries(keyValues);
+    }
+    else if(input.expressionAttributeFiles) {
+      const expAttValues = input.expressionAttributeFiles!.split(',');
+      const keyValues = [];
+
+      for(let i=0; i<updateExpressions.length; i++) {
+        updateExpressions[i] = updateExpressions[i].substring(updateExpressions[i].indexOf(":"));
+        keyValues[i] = [updateExpressions[i], await this.read(expAttValues[i])];
+      }
+
+      attValues = Object.fromEntries(keyValues);
+    }
+
+    return attValues;
+  }
+}
\ No newline at end of file
diff --git a/src/processor.ts b/src/processor.ts
index 009b6ea2..b5a6115f 100644
--- a/src/processor.ts
+++ b/src/processor.ts
@@ -1,6 +1,6 @@
 import { Operation, Output } from "./operations";
 
-import { BatchPutOperation, DeleteOperation, GetOperation, PutOperation } from "./operations";
+import { BatchPutOperation, DeleteOperation, GetOperation, PutOperation, UpdateOperation } from "./operations";
 
 export class Processor {
   public operations: Operation<any>[] = [
@@ -8,6 +8,7 @@ export class Processor {
     new DeleteOperation(),
     new GetOperation(),
     new PutOperation(),
+    new UpdateOperation()
   ];
 
   public async process(input: {