diff --git a/python/semantic_kernel/connectors/openapi_plugin/openapi_parser.py b/python/semantic_kernel/connectors/openapi_plugin/openapi_parser.py
index 848bba8386eb..0ed36f209d00 100644
--- a/python/semantic_kernel/connectors/openapi_plugin/openapi_parser.py
+++ b/python/semantic_kernel/connectors/openapi_plugin/openapi_parser.py
@@ -206,6 +206,7 @@ def create_rest_api_operations(
 
         paths = parsed_document.get("paths", {})
         request_objects = {}
+        unique_operation_ids_registered: set[str] = set()
 
         servers = parsed_document.get("servers", [])
 
@@ -230,7 +231,15 @@ def create_rest_api_operations(
         for path, methods in paths.items():
             for method, details in methods.items():
                 request_method = method.lower()
-                operationId = details.get("operationId", path + "_" + request_method)
+                # Validate that operationId exists
+                if "operationId" not in details:
+                    raise PluginInitializationError(f"operationId missing, path: '{path}', method: '{method}'")
+                operationId = details["operationId"]
+                if operationId in unique_operation_ids_registered:
+                    raise PluginInitializationError(
+                        f"Duplicate operationId: '{operationId}', path: '{path}', method: '{method}'"
+                    )
+                unique_operation_ids_registered.add(operationId)
 
                 summary = details.get("summary", None)
                 description = details.get("description", None)
diff --git a/python/tests/unit/connectors/openapi_plugin/duplicate-operationid-openapi.yaml b/python/tests/unit/connectors/openapi_plugin/duplicate-operationid-openapi.yaml
new file mode 100644
index 000000000000..62162de97859
--- /dev/null
+++ b/python/tests/unit/connectors/openapi_plugin/duplicate-operationid-openapi.yaml
@@ -0,0 +1,32 @@
+openapi: 3.0.3
+info:
+  title: Simple HTTPBin API
+  version: 1.0.0
+
+servers:
+  - url: https://httpbin.org
+
+paths:
+  /get:
+    get:
+      operationId: duplicateId
+      summary: Simple GET request to httpbin.org
+      responses:
+        '200':
+          description: Successful response from httpbin
+          content:
+            application/json:
+              schema:
+                type: object
+
+  /ip:
+    get:
+      operationId: duplicateId
+      summary: Get client IP address from httpbin
+      responses:
+        '200':
+          description: Successful response with IP
+          content:
+            application/json:
+              schema:
+                type: object
diff --git a/python/tests/unit/connectors/openapi_plugin/no-operationid-openapi.yaml b/python/tests/unit/connectors/openapi_plugin/no-operationid-openapi.yaml
new file mode 100644
index 000000000000..f621ca7d461b
--- /dev/null
+++ b/python/tests/unit/connectors/openapi_plugin/no-operationid-openapi.yaml
@@ -0,0 +1,17 @@
+openapi: 3.0.3
+info:
+  title: Simple HTTPBin API
+  version: 1.0.0
+servers:
+  - url: https://httpbin.org
+paths:
+  /get:
+    get:
+      summary: Simple GET request to httpbin.org
+      responses:
+        '200':
+          description: Successful response from httpbin
+          content:
+            application/json:
+              schema:
+                type: object