diff --git a/pymilvus/client/utils.py b/pymilvus/client/utils.py
index 9e51ad1c7..f6fa2831b 100644
--- a/pymilvus/client/utils.py
+++ b/pymilvus/client/utils.py
@@ -159,14 +159,16 @@ def check_invalid_binary_vector(entities: List) -> bool:
             if not isinstance(entity["values"], list) or len(entity["values"]) == 0:
                 return False
 
-            dim = len(entity["values"][0]) * 8
+            first = entity["values"][0]
+            if not isinstance(first, bytes):
+                return False
+
+            dim = len(first) * 8
             if dim == 0:
                 return False
 
             for values in entity["values"]:
-                if len(values) * 8 != dim:
-                    return False
-                if not isinstance(values, bytes):
+                if not isinstance(values, bytes) or len(values) * 8 != dim:
                     return False
     return True
 
diff --git a/tests/unit/test_utils.py b/tests/unit/test_utils.py
index fc82fdaa0..56e531ac4 100644
--- a/tests/unit/test_utils.py
+++ b/tests/unit/test_utils.py
@@ -255,6 +255,16 @@ def test_non_bytes_values(self):
         entities = [{"type": DataType.BINARY_VECTOR, "values": [[0, 1], [2, 3]]}]
         assert utils.check_invalid_binary_vector(entities) is False
 
+    def test_non_sized_values(self):
+        entities = [{"type": DataType.BINARY_VECTOR, "values": [None]}]
+        assert utils.check_invalid_binary_vector(entities) is False
+
+        entities = [{"type": DataType.BINARY_VECTOR, "values": [1, 2]}]
+        assert utils.check_invalid_binary_vector(entities) is False
+
+        entities = [{"type": DataType.BINARY_VECTOR, "values": [b"\x00\x01", None]}]
+        assert utils.check_invalid_binary_vector(entities) is False
+
     def test_empty_values(self):
         entities = [{"type": DataType.BINARY_VECTOR, "values": []}]
         assert utils.check_invalid_binary_vector(entities) is False