diff --git a/webapp/services/RoomBattleDataService.php b/webapp/services/RoomBattleDataService.php
index c28a410a..c63be2f3 100644
--- a/webapp/services/RoomBattleDataService.php
+++ b/webapp/services/RoomBattleDataService.php
@@ -286,18 +286,21 @@ class RoomBattleDataService extends BaseService {
                 $rnd = rand(1,100);
                 if ($rnd <= $rand){
                     $chestItems = LootService::dropOutItem($rewardMeta['chestLoot']);
-                    $event = array(
-                        'ID' => 'Box',
-                        'SUB_ID' => 'drop',
-                        'SUB_KEY' => 'drop_box',
-                        'before' =>array(
-                            'rnd' => $rnd,
-                            'rate' => $rate,
-                            'rewardMeta' => $rewardMeta,
-                        ),
-                        'result' => $chestItems,
-                    );
-                    LogService::burialPointEvent($event);
+                    if (count($chestItems)>0){
+                        $event = array(
+                            'ID' => 'Box',
+                            'SUB_ID' => 'drop',
+                            'SUB_KEY' => 'drop_box',
+                            'before' =>array(
+                                'rnd' => $rnd,
+                                'rate' => $rate,
+                                'rewardMeta' => $rewardMeta,
+                            ),
+                            'result' => $chestItems,
+                        );
+                        LogService::burialPointEvent($event);
+                    }
+
                     foreach ($chestItems as $item){
                         array_push($reward,$item);
                     }