diff --git a/google/cloud/spanner_v1/data_types.py b/google/cloud/spanner_v1/data_types.py
index 6703f359e9..07e4faa1c1 100644
--- a/google/cloud/spanner_v1/data_types.py
+++ b/google/cloud/spanner_v1/data_types.py
@@ -56,6 +56,56 @@ def __init__(self, *args, **kwargs):
         if not self._is_null:
             super(JsonObject, self).__init__(*args, **kwargs)
 
+    def __len__(self):
+        if self._is_null:
+            return 0
+        if self._is_array:
+            return len(self._array_value)
+        if self._is_scalar_value:
+            return 1
+        return super(JsonObject, self).__len__()
+
+    def __bool__(self):
+        if self._is_null:
+            return False
+        if self._is_array:
+            return bool(self._array_value)
+        if self._is_scalar_value:
+            return True
+        return len(self) > 0
+
+    def __iter__(self):
+        if self._is_array:
+            return iter(self._array_value)
+        if self._is_scalar_value:
+            raise TypeError(f"'{type(self._simple_value).__name__}' object is not iterable")
+        return super(JsonObject, self).__iter__()
+
+    def __getitem__(self, key):
+        if self._is_array:
+            return self._array_value[key]
+        if self._is_scalar_value:
+            raise TypeError(f"'{type(self._simple_value).__name__}' object is not subscriptable")
+        return super(JsonObject, self).__getitem__(key)
+
+    def __contains__(self, item):
+        if self._is_array:
+            return item in self._array_value
+        if self._is_scalar_value:
+            raise TypeError(f"argument of type '{type(self._simple_value).__name__}' is not iterable")
+        return super(JsonObject, self).__contains__(item)
+
+    def __eq__(self, other):
+        if isinstance(other, JsonObject):
+            return self.serialize() == other.serialize()
+        if self._is_array:
+            return self._array_value == other
+        if self._is_scalar_value:
+            return self._simple_value == other
+        if self._is_null:
+            return other is None or (isinstance(other, dict) and len(other) == 0)
+        return super(JsonObject, self).__eq__(other)
+
     def __repr__(self):
         if self._is_array:
             return str(self._array_value)
diff --git a/tests/unit/test_datatypes.py b/tests/unit/test_datatypes.py
index 65ccacb4ff..25cc834808 100644
--- a/tests/unit/test_datatypes.py
+++ b/tests/unit/test_datatypes.py
@@ -96,3 +96,90 @@ def test_w_JsonObject_of_list_of_simple_JsonData(self):
         expected = json.dumps(data, sort_keys=True, separators=(",", ":"))
         data_jsonobject = JsonObject(JsonObject(data))
         self.assertEqual(data_jsonobject.serialize(), expected)
+
+
+class Test_JsonObject_dict_protocol(unittest.TestCase):
+    """Verify that JsonObject behaves correctly with standard Python
+    operations (len, bool, iteration, indexing) for all JSON variants."""
+
+    def test_array_len(self):
+        obj = JsonObject([{"id": 1}, {"id": 2}])
+        self.assertEqual(len(obj), 2)
+
+    def test_array_bool_truthy(self):
+        obj = JsonObject([{"id": 1}])
+        self.assertTrue(obj)
+
+    def test_array_bool_empty(self):
+        obj = JsonObject([])
+        self.assertFalse(obj)
+
+    def test_array_iter(self):
+        data = [{"a": 1}, {"b": 2}]
+        obj = JsonObject(data)
+        self.assertEqual(list(obj), data)
+
+    def test_array_getitem(self):
+        data = [{"a": 1}, {"b": 2}]
+        obj = JsonObject(data)
+        self.assertEqual(obj[0], {"a": 1})
+        self.assertEqual(obj[1], {"b": 2})
+
+    def test_array_contains(self):
+        data = [1, 2, 3]
+        obj = JsonObject(data)
+        self.assertIn(2, obj)
+        self.assertNotIn(4, obj)
+
+    def test_array_eq(self):
+        data = [{"id": 1}]
+        obj = JsonObject(data)
+        self.assertEqual(obj, data)
+
+    def test_array_json_dumps(self):
+        data = [{"id": "m1", "content": "hello"}]
+        obj = JsonObject(data)
+        result = json.loads(json.dumps(list(obj)))
+        self.assertEqual(result, data)
+
+    def test_dict_len(self):
+        obj = JsonObject({"a": 1, "b": 2})
+        self.assertEqual(len(obj), 2)
+
+    def test_dict_bool(self):
+        obj = JsonObject({"a": 1})
+        self.assertTrue(obj)
+
+    def test_dict_iter(self):
+        obj = JsonObject({"a": 1, "b": 2})
+        self.assertEqual(sorted(obj), ["a", "b"])
+
+    def test_dict_getitem(self):
+        obj = JsonObject({"key": "value"})
+        self.assertEqual(obj["key"], "value")
+
+    def test_null_len(self):
+        obj = JsonObject(None)
+        self.assertEqual(len(obj), 0)
+
+    def test_null_bool(self):
+        obj = JsonObject(None)
+        self.assertFalse(obj)
+
+    def test_scalar_len(self):
+        obj = JsonObject(42)
+        self.assertEqual(len(obj), 1)
+
+    def test_scalar_bool(self):
+        obj = JsonObject(42)
+        self.assertTrue(obj)
+
+    def test_scalar_not_iterable(self):
+        obj = JsonObject(42)
+        with self.assertRaises(TypeError):
+            iter(obj)
+
+    def test_scalar_not_subscriptable(self):
+        obj = JsonObject(42)
+        with self.assertRaises(TypeError):
+            obj[0]