diff --git a/agv_app/app.py b/agv_app/app.py
index ce3de20..2ae9929 100644
--- a/agv_app/app.py
+++ b/agv_app/app.py
@@ -651,6 +651,11 @@ def api_mission_config_set():
     gs.mission_config["rows"] = rows
     gs.mission_config["cols"] = cols
     gs.mission_config["grid"] = grid
+    # 清除超出网格边界的 positions（只保留 front/back 且 row<rows, col<cols）
+    gs.mission_config["positions"] = [
+        p for p in gs.mission_config.get("positions", [])
+        if p.get("row", 0) < rows and p.get("col", 0) < cols and p.get("side") in ("front", "back")
+    ]
     save_json("mission_config.json", gs.mission_config)
     return jsonify({"ok": True, "config": gs.mission_config})