diff --git a/crates/loro-internal/src/handler/tree.rs b/crates/loro-internal/src/handler/tree.rs
index a29a49f9..dd8749a3 100644
--- a/crates/loro-internal/src/handler/tree.rs
+++ b/crates/loro-internal/src/handler/tree.rs
@@ -538,7 +538,10 @@ impl TreeHandler {
                 self.move_to(target, parent, index)
             }
             MaybeDetached::Attached(a) => {
-                let index: usize = self.children_num(&parent).unwrap_or(0);
+                let mut index: usize = self.children_num(&parent).unwrap_or(0);
+                if self.is_parent(&target, &parent) {
+                    index -= 1;
+                }
                 a.with_txn(|txn| {
                     self.mov_with_txn(txn, target, parent, index, FiIfNotConfigured::Zero)
                 })
diff --git a/crates/loro-internal/tests/tree.rs b/crates/loro-internal/tests/tree.rs
index 54d6ed69..8cdae51f 100644
--- a/crates/loro-internal/tests/tree.rs
+++ b/crates/loro-internal/tests/tree.rs
@@ -23,3 +23,13 @@ fn tree_index() {
     assert_eq!(tree.get_index_by_tree_id(&child).unwrap(), 1);
     assert_eq!(tree.get_index_by_tree_id(&child2).unwrap(), 0);
 }
+
+#[test]
+fn tree_move_in_parent() {
+    let doc = LoroDoc::new_auto_commit();
+    doc.set_peer_id(0).unwrap();
+    let tree = doc.get_tree("tree");
+    let root = tree.create(TreeParentId::Root).unwrap();
+    let child = tree.create(root.into()).unwrap();
+    tree.mov(child, root.into()).unwrap();
+}