diff --git a/include/msgpack/v1/adaptor/cpp11/timespec.hpp b/include/msgpack/v1/adaptor/cpp11/timespec.hpp
index c68294dec..dc047ee00 100644
--- a/include/msgpack/v1/adaptor/cpp11/timespec.hpp
+++ b/include/msgpack/v1/adaptor/cpp11/timespec.hpp
@@ -13,7 +13,6 @@
 #include "msgpack/versioning.hpp"
 #include "msgpack/adaptor/adaptor_base.hpp"
 #include "msgpack/object.hpp"
-#include "msgpack/object.hpp"
 
 #include <ctime>