diff --git a/seafile_sync/Dockerfile b/seafile_sync/Dockerfile
index 7f8b6d6..6950814 100644
--- a/seafile_sync/Dockerfile
+++ b/seafile_sync/Dockerfile
@@ -1,5 +1,2 @@
 # https://gitlab.com/flwgns-docker/seafile-client/
-ARG \
-    SEAF_SERVER_URL==${SEAF_SERVER_URL}
-
 FROM flowgunso/seafile-client:latest