diff --git a/backends/vulkan/runtime/graph/ComputeGraph.cpp b/backends/vulkan/runtime/graph/ComputeGraph.cpp
index b14d0f6ab0b..f0b61e128bb 100644
--- a/backends/vulkan/runtime/graph/ComputeGraph.cpp
+++ b/backends/vulkan/runtime/graph/ComputeGraph.cpp
@@ -1135,8 +1135,6 @@ void ComputeGraph::prepack() {
   int i = 0;
   bool submitted = false;
   const bool reduce_peak_memory = total_constant_nbytes_ > 10 * MB;
-  // int count = 0;
-
   context_->set_cmd();
   for (std::unique_ptr<PrepackNode>& node : prepack_nodes_) {
     // Do not trigger on the first or last prepack node.
diff --git a/backends/vulkan/runtime/graph/containers/Constant.h b/backends/vulkan/runtime/graph/containers/Constant.h
index a18c284a219..690a25dd9c8 100644
--- a/backends/vulkan/runtime/graph/containers/Constant.h
+++ b/backends/vulkan/runtime/graph/containers/Constant.h
@@ -29,6 +29,12 @@ struct TensorRef final {
   // This will be empty (default constructed) for the raw pointer constructor
   executorch::runtime::FreeableBuffer buffer;
 
+  // Number of PrepackNodes that still need to read from this TensorRef. When
+  // this reaches 0, the buffer can be safely freed. This prevents
+  // use-after-free when multiple PrepackNodes reference the same TensorRef
+  // (e.g. shared/tied weights).
+  int32_t prepack_use_count{0};
+
   explicit TensorRef(
       const std::vector<int64_t>& t_sizes,
       vkapi::ScalarType t_dtype,
@@ -44,8 +50,6 @@ struct TensorRef final {
     return utils::multiply_integers(sizes) * vkapi::element_size(dtype);
   }
 
-  // Manually free the buffer if needed (though it will be freed automatically
-  // on destruction)
   void free_buffer() {
     buffer.Free();
   }
diff --git a/backends/vulkan/runtime/graph/ops/PrepackNode.cpp b/backends/vulkan/runtime/graph/ops/PrepackNode.cpp
index bb21f4b7c2b..9d89a45e168 100644
--- a/backends/vulkan/runtime/graph/ops/PrepackNode.cpp
+++ b/backends/vulkan/runtime/graph/ops/PrepackNode.cpp
@@ -44,6 +44,9 @@ PrepackNode::PrepackNode(
       push_constants_(push_constants) {
   graph.update_descriptor_counts(shader, /*execute = */ false);
   graph.update_descriptor_counts(noop_shader_, /*execute = */ false);
+  if (!graph.val_is_none(tref)) {
+    graph.get_tref(tref)->prepack_use_count++;
+  }
 }
 
 api::StagingBuffer PrepackNode::create_staging_buffer(ComputeGraph* graph) {
@@ -100,9 +103,10 @@ api::StagingBuffer PrepackNode::create_staging_buffer(ComputeGraph* graph) {
     }
   }
 
-  // Once the staging buffer is copied, if the TensorRef owns a FreeableBuffer,
-  // it can be freed.
-  tref->free_buffer();
+  if (--tref->prepack_use_count == 0) {
+    tref->free_buffer();
+  }
+
   return staging;
 }