diff --git a/server/gameserver/gridcell.cc b/server/gameserver/gridcell.cc
index 7cedb22..2c4f979 100644
--- a/server/gameserver/gridcell.cc
+++ b/server/gameserver/gridcell.cc
@@ -5,6 +5,7 @@
 #include "entity.h"
 #include "human.h"
 #include "room.h"
+#include "car.h"
 
 GridCell::GridCell()
 {
@@ -24,6 +25,7 @@ void GridCell::ClearRoomData(Room* room)
     human_list_[room->GetRoomIdx()].clear();
     entity_list_[room->GetRoomIdx()].clear();
     bullet_list_[room->GetRoomIdx()].clear();
+    bullet_list_[room->GetRoomIdx()].clear();
 }
 
 void GridCell::AddHuman(Human* hum)
@@ -70,6 +72,16 @@ void GridCell::RemoveBullet(Bullet* bullet)
     bullet_list_[bullet->room->GetRoomIdx()].erase(bullet);
 }
 
+void GridCell::AddCar(Car* car)
+{
+    car_list_[car->room->GetRoomIdx()].insert(car);
+}
+
+void GridCell::RemoveCar(Car* car)
+{
+    car_list_[car->room->GetRoomIdx()].erase(car);
+}
+
 void GridCell::AddPermanentEntity(Entity* entity)
 {
     entity_list_[0].insert(entity);
diff --git a/server/gameserver/gridcell.h b/server/gameserver/gridcell.h
index 6b25e5b..f15e5db 100644
--- a/server/gameserver/gridcell.h
+++ b/server/gameserver/gridcell.h
@@ -4,6 +4,7 @@ class Entity;
 class Human;
 class Bullet;
 class Room;
+class Car;
 
 class GridCell
 {
@@ -23,6 +24,8 @@ public:
 
     void AddBullet(Bullet* bullet);
     void RemoveBullet(Bullet* bullet);
+    void AddCar(Car* car);
+    void RemoveCar(Car* car);
     void AddPermanentEntity(Entity* entity);
     void AddRoomEntity(Room* room, Entity* entity);
     void RemoveRoomEntity(Room* room, Entity* entity);
@@ -40,4 +43,5 @@ private:
     std::vector<std::set<Human*>> human_list_;
     std::vector<std::set<Entity*>> entity_list_;
     std::vector<std::set<Bullet*>> bullet_list_;
+    std::vector<std::set<Car*>> car_list_;
 };
diff --git a/server/gameserver/gridservice.cc b/server/gameserver/gridservice.cc
index 5b38ddc..9607a15 100644
--- a/server/gameserver/gridservice.cc
+++ b/server/gameserver/gridservice.cc
@@ -5,6 +5,7 @@
 #include "bullet.h"
 #include "room.h"
 #include "gridcell.h"
+#include "car.h"
 
 /*
   1 2 3
@@ -193,17 +194,50 @@ void GridService::DelBullet(Bullet* bullet)
 
 void GridService::AddCar(Car* car)
 {
-
+    int x = (int)car->GetX() + cell_width_;
+    int y = (int)car->GetY() + cell_width_;
+    if (BroderOverFlow(x, y)) {
+        abort();
+    }
+    car->SetGridId(x/cell_width_ + (y/cell_width_) * cell_count_per_row_);
+    if (car->GetGridId() == 0 || car->GetGridId() > max_grid_id_) {
+        abort();
+    }
+    cells_[car->GetGridId()].AddCar(car);
+    GetAllCells(car->room, car->GetGridId(), car->GetGridList());
 }
 
 void GridService::MoveCar(Car* car)
 {
-
+    int new_x = (int)car->GetX() + cell_width_;
+    int new_y = (int)car->GetY() + cell_width_;
+    int new_grid_id = new_x/cell_width_ + (new_y/cell_width_) * cell_count_per_row_;
+    if (BroderOverFlow(new_x, new_y)) {
+        abort();
+    }
+    if (new_grid_id == 0 || new_grid_id > max_grid_id_) {
+        abort();
+    }
+    if (new_grid_id != car->GetGridId()) {
+        std::set<GridCell*> inc_grid_list;
+        std::set<GridCell*> dec_grid_list;
+        std::set<GridCell*> old_grid_list = car->GetGridList();
+        ComputeDiff(car->room,
+                    car->GetGridId(),
+                    new_grid_id,
+                    car->GetGridList(),
+                    inc_grid_list,
+                    dec_grid_list);
+        cells_[car->GetGridId()].RemoveCar(car);
+        cells_[new_grid_id].AddCar(car);
+        car->SetGridId(new_grid_id);
+    }
 }
 
 void GridService::DelCar(Car* car)
 {
-
+    GridCell& cell = cells_[car->GetGridId()];
+    cell.RemoveCar(car);
 }
 
 void GridService::AddRoomEntity(Room* room, Entity* entity)