diff --git a/control/lane_departure_checker/include/lane_departure_checker/lane_departure_checker.hpp b/control/lane_departure_checker/include/lane_departure_checker/lane_departure_checker.hpp
index a59df6340ad00..fd21d18b98a64 100644
--- a/control/lane_departure_checker/include/lane_departure_checker/lane_departure_checker.hpp
+++ b/control/lane_departure_checker/include/lane_departure_checker/lane_departure_checker.hpp
@@ -70,6 +70,7 @@ struct Input
   lanelet::LaneletMapPtr lanelet_map{};
   LaneletRoute::ConstSharedPtr route{};
   lanelet::ConstLanelets route_lanelets{};
+  lanelet::ConstLanelets shoulder_lanelets{};
   Trajectory::ConstSharedPtr reference_trajectory{};
   Trajectory::ConstSharedPtr predicted_trajectory{};
 };
diff --git a/control/lane_departure_checker/include/lane_departure_checker/lane_departure_checker_node.hpp b/control/lane_departure_checker/include/lane_departure_checker/lane_departure_checker_node.hpp
index 8869825890b8b..53b5461652970 100644
--- a/control/lane_departure_checker/include/lane_departure_checker/lane_departure_checker_node.hpp
+++ b/control/lane_departure_checker/include/lane_departure_checker/lane_departure_checker_node.hpp
@@ -66,6 +66,7 @@ class LaneDepartureCheckerNode : public rclcpp::Node
   geometry_msgs::msg::PoseStamped::ConstSharedPtr current_pose_;
   nav_msgs::msg::Odometry::ConstSharedPtr current_odom_;
   lanelet::LaneletMapPtr lanelet_map_;
+  lanelet::ConstLanelets shoulder_lanelets_;
   lanelet::traffic_rules::TrafficRulesPtr traffic_rules_;
   lanelet::routing::RoutingGraphPtr routing_graph_;
   LaneletRoute::ConstSharedPtr route_;
diff --git a/control/lane_departure_checker/src/lane_departure_checker_node/lane_departure_checker.cpp b/control/lane_departure_checker/src/lane_departure_checker_node/lane_departure_checker.cpp
index db20dd7c8b981..e3e753d9e4023 100644
--- a/control/lane_departure_checker/src/lane_departure_checker_node/lane_departure_checker.cpp
+++ b/control/lane_departure_checker/src/lane_departure_checker_node/lane_departure_checker.cpp
@@ -123,7 +123,15 @@ Output LaneDepartureChecker::update(const Input & input)
   output.vehicle_passing_areas = createVehiclePassingAreas(output.vehicle_footprints);
   output.processing_time_map["createVehiclePassingAreas"] = stop_watch.toc(true);
 
-  output.candidate_lanelets = getCandidateLanelets(input.route_lanelets, output.vehicle_footprints);
+  const auto candidate_road_lanelets =
+    getCandidateLanelets(input.route_lanelets, output.vehicle_footprints);
+  const auto candidate_shoulder_lanelets =
+    getCandidateLanelets(input.shoulder_lanelets, output.vehicle_footprints);
+  output.candidate_lanelets = candidate_road_lanelets;
+  output.candidate_lanelets.insert(
+    output.candidate_lanelets.end(), candidate_shoulder_lanelets.begin(),
+    candidate_shoulder_lanelets.end());
+
   output.processing_time_map["getCandidateLanelets"] = stop_watch.toc(true);
 
   output.will_leave_lane = willLeaveLane(output.candidate_lanelets, output.vehicle_footprints);
diff --git a/control/lane_departure_checker/src/lane_departure_checker_node/lane_departure_checker_node.cpp b/control/lane_departure_checker/src/lane_departure_checker_node/lane_departure_checker_node.cpp
index d45fd2590a769..f0274e5c4712f 100644
--- a/control/lane_departure_checker/src/lane_departure_checker_node/lane_departure_checker_node.cpp
+++ b/control/lane_departure_checker/src/lane_departure_checker_node/lane_departure_checker_node.cpp
@@ -197,6 +197,10 @@ void LaneDepartureCheckerNode::onLaneletMapBin(const HADMapBin::ConstSharedPtr m
 {
   lanelet_map_ = std::make_shared<lanelet::LaneletMap>();
   lanelet::utils::conversion::fromBinMsg(*msg, lanelet_map_, &traffic_rules_, &routing_graph_);
+
+  // get all shoulder lanes
+  lanelet::ConstLanelets all_lanelets = lanelet::utils::query::laneletLayer(lanelet_map_);
+  shoulder_lanelets_ = lanelet::utils::query::shoulderLanelets(all_lanelets);
 }
 
 void LaneDepartureCheckerNode::onRoute(const LaneletRoute::ConstSharedPtr msg) { route_ = msg; }
@@ -313,6 +317,7 @@ void LaneDepartureCheckerNode::onTimer()
   input_.lanelet_map = lanelet_map_;
   input_.route = route_;
   input_.route_lanelets = route_lanelets_;
+  input_.shoulder_lanelets = shoulder_lanelets_;
   input_.reference_trajectory = reference_trajectory_;
   input_.predicted_trajectory = predicted_trajectory_;
   processing_time_map["Node: setInputData"] = stop_watch.toc(true);