diff --git a/python_modules/dagster-webserver/dagster_webserver/webserver.py b/python_modules/dagster-webserver/dagster_webserver/webserver.py
index 7f8f4a536f073..2ca19aada200a 100644
--- a/python_modules/dagster-webserver/dagster_webserver/webserver.py
+++ b/python_modules/dagster-webserver/dagster_webserver/webserver.py
@@ -292,6 +292,10 @@ def _static_file(path, file_path):
             # These are tested by an internal test without building the app.
             return [
                 Route("/favicon.png", lambda _: FileResponse(path="/favicon")),
+                Route(
+                    "/vendor/graphiql/graphiql.min.css",
+                    lambda _: FileResponse(path="/vendor/graphiql/graphiql.min.css"),
+                ),
             ]
 
         return routes