diff --git a/src/llmtuner/webui/chatter.py b/src/llmtuner/webui/chatter.py
index ee28603e..82e7b7f1 100644
--- a/src/llmtuner/webui/chatter.py
+++ b/src/llmtuner/webui/chatter.py
@@ -31,7 +31,10 @@ class WebChatModel(ChatModel):
         if demo_mode and os.environ.get("DEMO_MODEL") and os.environ.get("DEMO_TEMPLATE"):  # load demo model
             model_name_or_path = os.environ.get("DEMO_MODEL")
             template = os.environ.get("DEMO_TEMPLATE")
-            super().__init__(dict(model_name_or_path=model_name_or_path, template=template))
+            infer_backend = os.environ.get("DEMO_BACKEND", "huggingface")
+            super().__init__(
+                dict(model_name_or_path=model_name_or_path, template=template, infer_backend=infer_backend)
+            )
 
     @property
     def loaded(self) -> bool: