diff --git a/backend/open_webui/routers/images.py b/backend/open_webui/routers/images.py
index 275704f34..22fd8ac71 100644
--- a/backend/open_webui/routers/images.py
+++ b/backend/open_webui/routers/images.py
@@ -500,7 +500,11 @@ async def image_generations(
                     if form_data.size
                     else request.app.state.config.IMAGE_SIZE
                 ),
-                "response_format": "b64_json",
+                **(
+                    {"response_format": "b64_json"}
+                    if "gpt-image-1" in request.app.state.config.IMAGE_GENERATION_MODEL
+                    else {}
+                ),
             }
 
             # Use asyncio.to_thread for the requests.post call