diff --git a/perception/detected_object_validation/src/obstacle_pointcloud/obstacle_pointcloud_validator.cpp b/perception/detected_object_validation/src/obstacle_pointcloud/obstacle_pointcloud_validator.cpp
index 3fe527935c485..c5ecce714735b 100644
--- a/perception/detected_object_validation/src/obstacle_pointcloud/obstacle_pointcloud_validator.cpp
+++ b/perception/detected_object_validation/src/obstacle_pointcloud/obstacle_pointcloud_validator.cpp
@@ -38,7 +38,7 @@ namespace bg = boost::geometry;
 using Shape = autoware_perception_msgs::msg::Shape;
 using Polygon2d = autoware::universe_utils::Polygon2d;
 
-Validator::Validator(PointsNumThresholdParam & points_num_threshold_param)
+Validator::Validator(const PointsNumThresholdParam & points_num_threshold_param)
 {
   points_num_threshold_param_.min_points_num = points_num_threshold_param.min_points_num;
   points_num_threshold_param_.max_points_num = points_num_threshold_param.max_points_num;
diff --git a/perception/detected_object_validation/src/obstacle_pointcloud/obstacle_pointcloud_validator.hpp b/perception/detected_object_validation/src/obstacle_pointcloud/obstacle_pointcloud_validator.hpp
index 19b42ecf9055b..54129ff7fedf7 100644
--- a/perception/detected_object_validation/src/obstacle_pointcloud/obstacle_pointcloud_validator.hpp
+++ b/perception/detected_object_validation/src/obstacle_pointcloud/obstacle_pointcloud_validator.hpp
@@ -64,7 +64,7 @@ class Validator
   pcl::PointCloud<pcl::PointXYZ>::Ptr cropped_pointcloud_;
 
 public:
-  explicit Validator(PointsNumThresholdParam & points_num_threshold_param);
+  explicit Validator(const PointsNumThresholdParam & points_num_threshold_param);
   inline pcl::PointCloud<pcl::PointXYZ>::Ptr getDebugPointCloudWithinObject()
   {
     return cropped_pointcloud_;