diff --git a/jsk_pcl_ros_utils/CMakeLists.txt b/jsk_pcl_ros_utils/CMakeLists.txt
index 95bd3022ba..774e60ef12 100644
--- a/jsk_pcl_ros_utils/CMakeLists.txt
+++ b/jsk_pcl_ros_utils/CMakeLists.txt
@@ -287,6 +287,7 @@ if (CATKIN_ENABLE_TESTING)
   if(TARGET tests)
     add_dependencies(tests install_test_data)
   endif()
+  # Naming Rule: filename of rostest should be {EXECUTABLE_NAME}.test
   add_rostest(test/point_indices_to_cluster_point_indices.test)
   if("$ENV{ROS_DISTRO}" STRGREATER "hydro")
     # unexpected error