diff --git a/test/cpp/interop/interop_server.cc b/test/cpp/interop/interop_server.cc
index de875d8e783..f55d624b21c 100644
--- a/test/cpp/interop/interop_server.cc
+++ b/test/cpp/interop/interop_server.cc
@@ -331,7 +331,7 @@ void grpc::testing::interop::RunServer(
 void grpc::testing::interop::RunServer(
     std::shared_ptr<ServerCredentials> creds, const int port,
     ServerStartedCondition* server_started_condition) {
-  RunServer(creds, FLAGS_port, server_started_condition, nullptr);
+  RunServer(creds, port, server_started_condition, nullptr);
 }
 
 void grpc::testing::interop::RunServer(