diff --git a/crates/loro-internal/src/handler.rs b/crates/loro-internal/src/handler.rs
index 02ade94a..f0dba4fa 100644
--- a/crates/loro-internal/src/handler.rs
+++ b/crates/loro-internal/src/handler.rs
@@ -620,6 +620,13 @@ impl ListHandler {
         pos: usize,
         c_type: ContainerType,
     ) -> LoroResult<Handler> {
+        if pos > self.len() {
+            return Err(LoroError::OutOfBound {
+                pos,
+                len: self.len(),
+            });
+        }
+
         let id = txn.next_id();
         let container_id = ContainerID::new_normal(id, c_type);
         let child_idx = txn.arena.register_container(&container_id);
diff --git a/crates/loro-internal/tests/test.rs b/crates/loro-internal/tests/test.rs
index 37b60be7..2268a181 100644
--- a/crates/loro-internal/tests/test.rs
+++ b/crates/loro-internal/tests/test.rs
@@ -6,6 +6,37 @@ use loro_internal::{
 };
 use serde_json::json;
 
+#[test]
+fn out_of_bound_test() {
+    let a = LoroDoc::new_auto_commit();
+    a.get_text("text").insert_(0, "Hello").unwrap();
+    a.get_list("list").insert_(0, "Hello".into()).unwrap();
+    a.get_list("list").insert_(1, "Hello".into()).unwrap();
+    // expect out of bound err
+    let err = a.get_text("text").insert_(6, "Hello").unwrap_err();
+    assert!(matches!(err, loro_common::LoroError::OutOfBound { .. }));
+    let err = a.get_text("text").delete_(3, 5).unwrap_err();
+    assert!(matches!(err, loro_common::LoroError::OutOfBound { .. }));
+    let err = a
+        .get_text("text")
+        .mark_(0, 8, "h", 5.into(), TextStyleInfoFlag::BOLD)
+        .unwrap_err();
+    assert!(matches!(err, loro_common::LoroError::OutOfBound { .. }));
+    let _err = a
+        .get_text("text")
+        .mark_(3, 0, "h", 5.into(), TextStyleInfoFlag::BOLD)
+        .unwrap_err();
+    let err = a.get_list("list").insert_(6, "Hello".into()).unwrap_err();
+    assert!(matches!(err, loro_common::LoroError::OutOfBound { .. }));
+    let err = a.get_list("list").delete_(3, 2).unwrap_err();
+    assert!(matches!(err, loro_common::LoroError::OutOfBound { .. }));
+    let err = a
+        .get_list("list")
+        .insert_container_(3, ContainerType::Map)
+        .unwrap_err();
+    assert!(matches!(err, loro_common::LoroError::OutOfBound { .. }));
+}
+
 #[test]
 fn list() {
     let a = LoroDoc::new_auto_commit();