diff --git a/vllm/entrypoints/openai/api_server.py b/vllm/entrypoints/openai/api_server.py
index e550943c88725..32282bfd8d12b 100644
--- a/vllm/entrypoints/openai/api_server.py
+++ b/vllm/entrypoints/openai/api_server.py
@@ -127,7 +127,8 @@ async def create_completion(request: CompletionRequest, raw_request: Request):
 
         @app.middleware("http")
         async def authentication(request: Request, call_next):
-            if not request.url.path.startswith("/v1"):
+            root_path = "" if args.root_path is None else args.root_path
+            if not request.url.path.startswith(f"{root_path}/v1"):
                 return await call_next(request)
             if request.headers.get("Authorization") != "Bearer " + token:
                 return JSONResponse(content={"error": "Unauthorized"},