diff --git a/src/backend/base/langflow/schema/message.py b/src/backend/base/langflow/schema/message.py
index c03c0cb71..5ad7d1922 100644
--- a/src/backend/base/langflow/schema/message.py
+++ b/src/backend/base/langflow/schema/message.py
@@ -41,6 +41,12 @@ class Message(Data):
             value = str(value)
         return value
 
+    @field_serializer("flow_id")
+    def serialize_flow_id(value):
+        if isinstance(value, str):
+            return UUID(value)
+        return value
+
     @field_validator("files", mode="before")
     @classmethod
     def validate_files(cls, value):