diff --git a/image_proc/include/image_proc/track_marker.hpp b/image_proc/include/image_proc/track_marker.hpp
index 6c212913f..87e310060 100644
--- a/image_proc/include/image_proc/track_marker.hpp
+++ b/image_proc/include/image_proc/track_marker.hpp
@@ -55,7 +55,6 @@ class TrackMarkerNode : public rclcpp::Node
 private:
   image_transport::CameraSubscriber sub_camera_;
 
-  int queue_size_;
   int marker_id_;
   double marker_size_;
   std::string image_topic_;