diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 28f2b39..a5c8562 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -963,17 +963,28 @@
 			struct btrfs_fs_info *fs_info, u64 qgroupid)
 {
 	struct btrfs_root *quota_root;
+	struct btrfs_qgroup *qgroup;
 	int ret = 0;
 
 	quota_root = fs_info->quota_root;
 	if (!quota_root)
 		return -EINVAL;
 
+	/* check if there are no relations to this qgroup */
+	spin_lock(&fs_info->qgroup_lock);
+	qgroup = find_qgroup_rb(fs_info, qgroupid);
+	if (qgroup) {
+		if (!list_empty(&qgroup->groups) || !list_empty(&qgroup->members)) {
+			spin_unlock(&fs_info->qgroup_lock);
+			return -EBUSY;
+		}
+	}
+	spin_unlock(&fs_info->qgroup_lock);
+
 	ret = del_qgroup_item(trans, quota_root, qgroupid);
 
 	spin_lock(&fs_info->qgroup_lock);
 	del_qgroup_rb(quota_root->fs_info, qgroupid);
-
 	spin_unlock(&fs_info->qgroup_lock);
 
 	return ret;