diff --git a/modules/openapi-generator/src/main/resources/python-pydantic-v1/api_client.mustache b/modules/openapi-generator/src/main/resources/python-pydantic-v1/api_client.mustache
index fe61bd61a5ed..7c7bfcdc7d5b 100644
--- a/modules/openapi-generator/src/main/resources/python-pydantic-v1/api_client.mustache
+++ b/modules/openapi-generator/src/main/resources/python-pydantic-v1/api_client.mustache
@@ -577,7 +577,7 @@ class ApiClient:
             if k in collection_formats:
                 collection_format = collection_formats[k]
                 if collection_format == 'multi':
-                    new_params.extend((k, value) for value in v)
+                    new_params.extend((k, str(value)) for value in v)
                 else:
                     if collection_format == 'ssv':
                         delimiter = ' '
diff --git a/modules/openapi-generator/src/main/resources/python/api_client.mustache b/modules/openapi-generator/src/main/resources/python/api_client.mustache
index 8c9812db7d2b..83b21860d554 100644
--- a/modules/openapi-generator/src/main/resources/python/api_client.mustache
+++ b/modules/openapi-generator/src/main/resources/python/api_client.mustache
@@ -491,7 +491,7 @@ class ApiClient:
             if k in collection_formats:
                 collection_format = collection_formats[k]
                 if collection_format == 'multi':
-                    new_params.extend((k, value) for value in v)
+                    new_params.extend((k, str(value)) for value in v)
                 else:
                     if collection_format == 'ssv':
                         delimiter = ' '