diff --git a/perception/ground_segmentation/config/ground_segmentation.param.yaml b/perception/ground_segmentation/config/ground_segmentation.param.yaml
index 594ef1fe974b2..779b73f738a39 100644
--- a/perception/ground_segmentation/config/ground_segmentation.param.yaml
+++ b/perception/ground_segmentation/config/ground_segmentation.param.yaml
@@ -11,8 +11,8 @@
         max_x: 100.0
         min_y: -50.0
         max_y: 50.0
-        max_z: 2.5  # recommended 2.5 for non elevation_grid_mode
-        min_z: -2.5 # recommended 0.0 for non elevation_grid_mode
+        margin_max_z: 0.0   # to extend the crop box min_z from ground. recommended 0.0 for non elevation_grid_mode
+        margin_min_z: -2.5  # to extend the crop box min_z from ground. recommended 0.0 for non elevation_Grid_mode
         negative: False
 
     common_ground_filter: