diff --git a/evaluator/autoware_planning_evaluator/src/metrics/deviation_metrics.cpp b/evaluator/autoware_planning_evaluator/src/metrics/deviation_metrics.cpp
index 82ba86c65d6af..9b5959948f8cb 100644
--- a/evaluator/autoware_planning_evaluator/src/metrics/deviation_metrics.cpp
+++ b/evaluator/autoware_planning_evaluator/src/metrics/deviation_metrics.cpp
@@ -58,7 +58,8 @@ Accumulator<double> calcLocalLateralTrajectoryDisplacement(
     autoware::motion_utils::calcLateralOffset(prev.points, ego_pose.position);
   const auto traj_lateral_deviation =
     autoware::motion_utils::calcLateralOffset(traj.points, ego_pose.position);
-  const auto lateral_trajectory_displacement = traj_lateral_deviation - prev_lateral_deviation;
+  const auto lateral_trajectory_displacement =
+    std::abs(traj_lateral_deviation - prev_lateral_deviation);
   stat.add(lateral_trajectory_displacement);
   return stat;
 }