diff --git a/weed/cluster/lock_manager/lock_manager.go b/weed/cluster/lock_manager/lock_manager.go
index 0e3e47ba4..49b951dd9 100644
--- a/weed/cluster/lock_manager/lock_manager.go
+++ b/weed/cluster/lock_manager/lock_manager.go
@@ -139,7 +139,7 @@ func (lm *LockManager) InsertLock(path string, expiredAtNs int64, token string,
 
 func (lm *LockManager) GetLockOwner(key string) (owner string, err error) {
 	lm.locks.Range(func(k string, lock *Lock) bool {
-		if k == key {
+		if k == key && lock != nil {
 			owner = lock.Owner
 			return false
 		}