diff --git a/dao/checkin.go b/dao/checkin.go
index 6a11a01..f6827b4 100644
--- a/dao/checkin.go
+++ b/dao/checkin.go
@@ -74,10 +74,11 @@ func (c CheckinDAO) SaveUserActivity(userActivity *po.UserActivity) {
 func (c CheckinDAO) FindAllActivities(isTeacher bool) []po.Activity {
 	var arr []po.Activity
 	var err error
+	// 按照主键排序
 	if isTeacher {
-		err = c.Tx.Find(&arr, "teacher_available=?", true).Error
+		err = c.Tx.Find(&arr, "teacher_available=?", true).Order("id").Error
 	} else {
-		err = c.Tx.Find(&arr).Error
+		err = c.Tx.Find(&arr).Order("id").Error
 	}
 	if err != nil {
 		panic(err)