diff --git a/src/tateyama/tgctl/main.cpp b/src/tateyama/tgctl/main.cpp
index 00085f8..9cdb8fc 100644
--- a/src/tateyama/tgctl/main.cpp
+++ b/src/tateyama/tgctl/main.cpp
@@ -86,6 +86,9 @@ int tgctl_main(const std::vector<std::string>& args) {
         return -1;
     }
     if (args.at(1) == "restore") {
+        if (FLAGS_timeout != -1) {
+            std::cerr << "timeout option cannot be specified to restore subcommand" << std::endl;
+        }
         FLAGS_timeout = 0;  // no timeout for 'tgctl restore xxx'
         tateyama::process::tgctl_start(args.at(0), true, tateyama::framework::boot_mode::maintenance_server);