diff --git a/modules/openapi-generator/src/main/resources/python-pydantic-v1/asyncio/rest.mustache b/modules/openapi-generator/src/main/resources/python-pydantic-v1/asyncio/rest.mustache
index c97788d0c5cc..9be766ce5771 100644
--- a/modules/openapi-generator/src/main/resources/python-pydantic-v1/asyncio/rest.mustache
+++ b/modules/openapi-generator/src/main/resources/python-pydantic-v1/asyncio/rest.mustache
@@ -143,6 +143,11 @@ class RESTClientObject:
                                        filename=v[0],
                                        content_type=v[2])
                     else:
+                        # Ensures that dict objects are serialized
+                        if isinstance(v, dict):
+                            v = json.dumps(v)
+                        elif isinstance(v, int):
+                            v = str(v)
                         data.add_field(k, v)
                 args["data"] = data
 
diff --git a/modules/openapi-generator/src/main/resources/python-pydantic-v1/rest.mustache b/modules/openapi-generator/src/main/resources/python-pydantic-v1/rest.mustache
index 1d6d255d2cd5..845324e199b8 100644
--- a/modules/openapi-generator/src/main/resources/python-pydantic-v1/rest.mustache
+++ b/modules/openapi-generator/src/main/resources/python-pydantic-v1/rest.mustache
@@ -190,6 +190,8 @@ class RESTClientObject:
                     # Content-Type which generated by urllib3 will be
                     # overwritten.
                     del headers['Content-Type']
+                    # Ensures that dict objects are serialized
+                    post_params = [(a, json.dumps(b)) if isinstance(b, dict) else (a,b) for a, b in post_params]
                     r = self.pool_manager.request(
                         method, url,
                         fields=post_params,
diff --git a/samples/client/echo_api/python-pydantic-v1/openapi_client/rest.py b/samples/client/echo_api/python-pydantic-v1/openapi_client/rest.py
index f4a710085985..8538f9ee5200 100644
--- a/samples/client/echo_api/python-pydantic-v1/openapi_client/rest.py
+++ b/samples/client/echo_api/python-pydantic-v1/openapi_client/rest.py
@@ -201,6 +201,8 @@ def request(self, method, url, query_params=None, headers=None,
                     # Content-Type which generated by urllib3 will be
                     # overwritten.
                     del headers['Content-Type']
+                    # Ensures that dict objects are serialized
+                    post_params = [(a, json.dumps(b)) if isinstance(b, dict) else (a,b) for a, b in post_params]
                     r = self.pool_manager.request(
                         method, url,
                         fields=post_params,
diff --git a/samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/petstore_api/rest.py b/samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/petstore_api/rest.py
index 7daf8c921c84..c71fbc6dea92 100644
--- a/samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/petstore_api/rest.py
+++ b/samples/openapi3/client/petstore/python-pydantic-v1-aiohttp/petstore_api/rest.py
@@ -153,6 +153,11 @@ async def request(self, method, url, query_params=None, headers=None,
                                        filename=v[0],
                                        content_type=v[2])
                     else:
+                        # Ensures that dict objects are serialized
+                        if isinstance(v, dict):
+                            v = json.dumps(v)
+                        elif isinstance(v, int):
+                            v = str(v)
                         data.add_field(k, v)
                 args["data"] = data
 
diff --git a/samples/openapi3/client/petstore/python-pydantic-v1/petstore_api/rest.py b/samples/openapi3/client/petstore/python-pydantic-v1/petstore_api/rest.py
index fcbbdab49ab9..a4a233273c5e 100644
--- a/samples/openapi3/client/petstore/python-pydantic-v1/petstore_api/rest.py
+++ b/samples/openapi3/client/petstore/python-pydantic-v1/petstore_api/rest.py
@@ -200,6 +200,8 @@ def request(self, method, url, query_params=None, headers=None,
                     # Content-Type which generated by urllib3 will be
                     # overwritten.
                     del headers['Content-Type']
+                    # Ensures that dict objects are serialized
+                    post_params = [(a, json.dumps(b)) if isinstance(b, dict) else (a,b) for a, b in post_params]
                     r = self.pool_manager.request(
                         method, url,
                         fields=post_params,