diff --git a/webapp/services/MissionService.php b/webapp/services/MissionService.php
index cb718569..acc6c541 100644
--- a/webapp/services/MissionService.php
+++ b/webapp/services/MissionService.php
@@ -666,6 +666,19 @@ class MissionService extends BaseService {
             $this->_rspErr(1, 'mission_id parameter error2');
             return;
         }
+        $missionMeta = mt\Task::get($missionId);
+        if (!$missionMeta) {
+            $this->_rspErr(1, 'mission_id parameter error2');
+            return;
+        }
+        if ($this->_getItemCount(V_ITEM_DIAMOND, $this->userInfo) < $missionMeta['boost']){
+            $this->_rspErr(2, 'diamond not enough');
+            return;
+        }
+        $this->_decItems(array(
+            'item_id' => V_ITEM_DIAMOND,
+            'item_num' => $missionMeta['boost']
+        ));
         $this->saveOfferRewardMission();
     }