diff --git a/nonebot/utils.py b/nonebot/utils.py
index e0900d12..688d0269 100644
--- a/nonebot/utils.py
+++ b/nonebot/utils.py
@@ -145,7 +145,7 @@ class DataclassEncoder(json.JSONEncoder):
     @overrides(json.JSONEncoder)
     def default(self, o):
         if dataclasses.is_dataclass(o):
-            return dataclasses.asdict(o)
+            return {f.name: getattr(o, f.name) for f in dataclasses.fields(o)}
         return super().default(o)
 
 
diff --git a/tests/test_utils.py b/tests/test_utils.py
new file mode 100644
index 00000000..d8936090
--- /dev/null
+++ b/tests/test_utils.py
@@ -0,0 +1,18 @@
+import json
+from utils import make_fake_message
+
+
+def test_dataclass_encoder():
+    from nonebot.utils import DataclassEncoder
+
+    MessageSegment = make_fake_message().get_segment_class()
+    ms = MessageSegment.node_custom(
+        "1234", "testtest", "test" + MessageSegment.image("url")
+    )
+    s = json.dumps(ms, cls = DataclassEncoder)
+    assert (
+        s
+        == '{"type": "node", "data": {"user_id": "1234", "nickname": "testtest", "content": [{"type": "text", "data": {"text": "test"}}, {"type": "image", "data": {"url": "url"}}]}}'
+    )
+    s1 = json.dumps("123", cls = DataclassEncoder)
+    assert s1 == '"123"'
\ No newline at end of file
diff --git a/tests/utils.py b/tests/utils.py
index 0cd94be4..e33ce5be 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -32,6 +32,16 @@ def make_fake_message():
         def image(url: str):
             return FakeMessageSegment("image", {"url": url})
 
+        @staticmethod
+        def node_custom(
+            user_id: str,
+            nickname: str,
+            content: Union["FakeMessage", "FakeMessageSegment", str],
+        ):
+            return FakeMessageSegment(
+                "node", {"user_id": user_id, "nickname": nickname, "content": content}
+            )
+
         def is_text(self) -> bool:
             return self.type == "text"