diff --git a/src/main/java/com/be/sportizebe/domain/user/controller/UserController.java b/src/main/java/com/be/sportizebe/domain/user/controller/UserController.java
index 2eb49b5..e423bd3 100644
--- a/src/main/java/com/be/sportizebe/domain/user/controller/UserController.java
+++ b/src/main/java/com/be/sportizebe/domain/user/controller/UserController.java
@@ -29,8 +29,17 @@ public class UserController {
 
     private final UserServiceImpl userService;
 
+    @GetMapping("/check-username")
+    @Operation(summary = "아이디 중복 체크", description = "사용 가능하면 false, 이미 사용 중이면 true 반환")
+    public ResponseEntity<BaseResponse<Boolean>> checkUsernameDuplicate(
+        @RequestParam String username
+    ) {
+        boolean isDuplicate = userService.checkUsernameDuplicate(username);
+        return ResponseEntity.ok(BaseResponse.success("아이디 중복 체크 성공", isDuplicate));
+    }
+
     @PostMapping("/signup")
-    @Operation(summary = "회원가입", description = "이메일과 비밀번호로 회원가입")
+    @Operation(summary = "회원가입", description = "아이디와 비밀번호로 회원가입")
     public ResponseEntity<BaseResponse<SignUpResponse>> signUp(@RequestBody @Valid SignUpRequest request) {
         SignUpResponse response = userService.signUp(request);
         return ResponseEntity.status(HttpStatus.CREATED)
diff --git a/src/main/java/com/be/sportizebe/domain/user/dto/request/SignUpRequest.java b/src/main/java/com/be/sportizebe/domain/user/dto/request/SignUpRequest.java
index b393eae..e22af72 100644
--- a/src/main/java/com/be/sportizebe/domain/user/dto/request/SignUpRequest.java
+++ b/src/main/java/com/be/sportizebe/domain/user/dto/request/SignUpRequest.java
@@ -1,15 +1,16 @@
 package com.be.sportizebe.domain.user.dto.request;
 
+import com.be.sportizebe.common.enums.SportType;
 import com.be.sportizebe.domain.user.entity.Gender;
 import io.swagger.v3.oas.annotations.media.Schema;
-import jakarta.validation.constraints.Email;
 import jakarta.validation.constraints.NotBlank;
 import jakarta.validation.constraints.Size;
 
+import java.util.List;
+
 public record SignUpRequest(
-    @Schema(description = "사용자 아이디(이메일 형식)", example = "user@example.com")
+    @Schema(description = "사용자 아이디", example = "sportize_user")
     @NotBlank(message = "아이디를 입력해주세요.")
-    @Email(message = "아이디는 이메일 형식만 지원합니다.")
     String username,
 
     @Schema(description = "비밀번호", example = "password123")
@@ -26,6 +27,9 @@ public record SignUpRequest(
 
     @Schema(description = "전화번호", example = "010-xxxx-xxxx")
     @NotBlank(message = "전화번호를 입력해주세요")
-    String phoneNumber
+    String phoneNumber,
+
+    @Schema(description = "관심 종목 목록 (선택)", example = "[\"SOCCER\", \"BASKETBALL\"]")
+    List<SportType> interestSports
 ) {
 }
\ No newline at end of file
diff --git a/src/main/java/com/be/sportizebe/domain/user/dto/response/SignUpResponse.java b/src/main/java/com/be/sportizebe/domain/user/dto/response/SignUpResponse.java
index 7473c87..560a0a8 100644
--- a/src/main/java/com/be/sportizebe/domain/user/dto/response/SignUpResponse.java
+++ b/src/main/java/com/be/sportizebe/domain/user/dto/response/SignUpResponse.java
@@ -8,7 +8,7 @@ public record SignUpResponse(
     @Schema(description = "사용자 식별자", example = "1")
     Long userId,
 
-    @Schema(description = "사용자 아이디(이메일 형식)", example = "user@example.com")
+    @Schema(description = "사용자 아이디", example = "sportize_user")
     String username,
 
     @Schema(description = "사용자 권한", example = "USER")
diff --git a/src/main/java/com/be/sportizebe/domain/user/entity/User.java b/src/main/java/com/be/sportizebe/domain/user/entity/User.java
index 8461eec..22364df 100644
--- a/src/main/java/com/be/sportizebe/domain/user/entity/User.java
+++ b/src/main/java/com/be/sportizebe/domain/user/entity/User.java
@@ -43,8 +43,12 @@ public class User extends BaseTimeEntity {
     @Enumerated(EnumType.STRING)
     private Role role;
 
+    @ElementCollection(fetch = FetchType.LAZY)
+    @CollectionTable(name = "user_interest_types", joinColumns = @JoinColumn(name = "user_id"))
+    @Column(name = "sport_type")
     @Enumerated(EnumType.STRING)
-    private List<SportType> interestType; // 사용자 관심 종목
+    @Builder.Default
+    private List<SportType> interestType = new ArrayList<>(); // 사용자 관심 종목
 
     private String profileImage; // 프로필 사진 URL
 
diff --git a/src/main/java/com/be/sportizebe/domain/user/service/UserService.java b/src/main/java/com/be/sportizebe/domain/user/service/UserService.java
index 8d2267d..5eea1e0 100644
--- a/src/main/java/com/be/sportizebe/domain/user/service/UserService.java
+++ b/src/main/java/com/be/sportizebe/domain/user/service/UserService.java
@@ -25,4 +25,7 @@ public interface UserService {
 
   // 비밀번호 변경
   void changePassword(Long userId, ChangePasswordRequest request);
+
+  // 아이디 중복 체크
+  boolean checkUsernameDuplicate(String username);
 }
diff --git a/src/main/java/com/be/sportizebe/domain/user/service/UserServiceImpl.java b/src/main/java/com/be/sportizebe/domain/user/service/UserServiceImpl.java
index ed07490..ad53243 100644
--- a/src/main/java/com/be/sportizebe/domain/user/service/UserServiceImpl.java
+++ b/src/main/java/com/be/sportizebe/domain/user/service/UserServiceImpl.java
@@ -55,6 +55,7 @@ public SignUpResponse signUp(SignUpRequest request) {
           .phoneNumber(request.phoneNumber())
           .gender(request.gender())
           .role(Role.USER)
+          .interestType(request.interestSports() != null ? request.interestSports() : new java.util.ArrayList<>())
           .build();
 
         User savedUser = userRepository.save(user);
@@ -121,6 +122,11 @@ public UserInfoResponse getUserInfo(Long userId) {
         return UserInfoResponse.from(userAuthInfo);
     }
 
+    @Override
+    public boolean checkUsernameDuplicate(String username) {
+        return userRepository.existsByUsername(username);
+    }
+
     @Override
     @Transactional
     public void changePassword(Long userId, ChangePasswordRequest request) {