diff --git a/modules/planning/conf/planning_config.pb.txt b/modules/planning/conf/planning_config.pb.txt
index 02d2bd2b8c3..82ef1382ff2 100644
--- a/modules/planning/conf/planning_config.pb.txt
+++ b/modules/planning/conf/planning_config.pb.txt
@@ -36,7 +36,7 @@ em_planner_config {
     dp_st_speed_config {
         total_path_length: 150
         total_time: 8.0
-        matrix_dimension_s: 400
+        matrix_dimension_s: 150
         matrix_dimension_t: 8
 
         speed_weight: 0.0