diff --git a/packages/grpc-js-xds/scripts/xds_k8s_url_map.sh b/packages/grpc-js-xds/scripts/xds_k8s_url_map.sh
index 901938ad..8b07b655 100644
--- a/packages/grpc-js-xds/scripts/xds_k8s_url_map.sh
+++ b/packages/grpc-js-xds/scripts/xds_k8s_url_map.sh
@@ -40,7 +40,7 @@ build_test_app_docker_images() {
 
   pushd "${SRC_DIR}"
   docker build \
-    -f src/python/grpcio_tests/tests_py3_only/interop/Dockerfile.client \
+    -f "${BUILD_APP_PATH}" \
     -t "${CLIENT_IMAGE_NAME}:${GIT_COMMIT}" \
     .