diff --git a/api/app/lib/controllers/project/bind.js b/api/app/lib/controllers/project/bind.js
index d2f81dd..aad724c 100644
--- a/api/app/lib/controllers/project/bind.js
+++ b/api/app/lib/controllers/project/bind.js
@@ -19,8 +19,8 @@ async function bindAnxin2pep (ctx) {
          name, pepProjectId, anxinProjectId,
          updateTime: now, mappingClass,
          del: false,
-         maintenanceEnd:maintenancePeriod&&maintenancePeriod.length?maintenancePeriod[1]:'',
-         maintenanceStart:maintenancePeriod&&maintenancePeriod.length?maintenancePeriod[0]:''
+         maintenanceEnd:maintenancePeriod&&maintenancePeriod.length?maintenancePeriod[1]:NULL,
+         maintenanceStart:maintenancePeriod&&maintenancePeriod.length?maintenancePeriod[0]:NULL
       }
 
       // 仅限已有 pepProjectId 的项目