diff --git a/test/cpp/end2end/proto_server_reflection_test.cc b/test/cpp/end2end/proto_server_reflection_test.cc
index efbb0e1f8e5f662017149b9bb379ed1d7d1654fa..75efd01f066e16e0c85b8b58e175332cb41d19dd 100644
--- a/test/cpp/end2end/proto_server_reflection_test.cc
+++ b/test/cpp/end2end/proto_server_reflection_test.cc
@@ -144,7 +144,7 @@ class ProtoServerReflectionTest : public ::testing::Test {
 TEST_F(ProtoServerReflectionTest, CheckResponseWithLocalDescriptorPool) {
   ResetStub();
 
-  std::vector<std::string> services;
+  std::vector<grpc::string> services;
   desc_db_->GetServices(&services);
   // The service list has at least one service (reflection servcie).
   EXPECT_TRUE(services.size() > 0);