diff --git a/block/snapshot.c b/block/snapshot.c
index 85c52ff4559e9158e36380195152e5eb3a03bf2e..698e1a1d5881cd92ba6c0aae832db687e20d7fd3 100644
--- a/block/snapshot.c
+++ b/block/snapshot.c
@@ -236,6 +236,10 @@ int bdrv_snapshot_delete(BlockDriverState *bs,
         error_setg(errp, "snapshot_id and name are both NULL");
         return -EINVAL;
     }
+
+    /* drain all pending i/o before deleting snapshot */
+    bdrv_drain_all();
+
     if (drv->bdrv_snapshot_delete) {
         return drv->bdrv_snapshot_delete(bs, snapshot_id, name, errp);
     }