diff --git a/kernel/api/storage.go b/kernel/api/storage.go
index fa223bc61..1cfe617a8 100644
--- a/kernel/api/storage.go
+++ b/kernel/api/storage.go
@@ -21,6 +21,7 @@ import (
 
 	"github.com/88250/gulu"
 	"github.com/gin-gonic/gin"
+	"github.com/siyuan-note/logging"
 	"github.com/siyuan-note/siyuan/kernel/model"
 	"github.com/siyuan-note/siyuan/kernel/util"
 )
@@ -177,6 +178,13 @@ func setLocalStorage(c *gin.Context) {
 		return
 	}
 
+	if arg["app"] == nil {
+		logging.LogErrorf("app is nil in setLocalStorage")
+		ret.Code = -1
+		ret.Msg = "arg [app] is nil"
+		return
+	}
+
 	app := arg["app"].(string)
 	evt := util.NewCmdResult("setLocalStorage", 0, util.PushModeBroadcastMainExcludeSelfApp)
 	evt.AppId = app