diff --git a/app/modules/bangumi/__init__.py b/app/modules/bangumi/__init__.py
index 6bf1ed56..7983e333 100644
--- a/app/modules/bangumi/__init__.py
+++ b/app/modules/bangumi/__init__.py
@@ -241,14 +241,7 @@ class BangumiModule(_ModuleBase):
         """
         personinfo = self.bangumiapi.person_detail(person_id)
         if personinfo:
-            return schemas.MediaPerson(source='bangumi', **{
-                "id": personinfo.get("id"),
-                "name": personinfo.get("name"),
-                "images": personinfo.get("images"),
-                "biography": personinfo.get("summary"),
-                "birthday": personinfo.get("birth_day"),
-                "gender": personinfo.get("gender")
-            })
+            return self._build_person_detail(personinfo)
         return None
 
     async def async_bangumi_person_detail(self, person_id: int) -> Optional[schemas.MediaPerson]:
@@ -258,16 +251,36 @@ class BangumiModule(_ModuleBase):
         """
         personinfo = await self.bangumiapi.async_person_detail(person_id)
         if personinfo:
-            return schemas.MediaPerson(source='bangumi', **{
-                "id": personinfo.get("id"),
-                "name": personinfo.get("name"),
-                "images": personinfo.get("images"),
-                "biography": personinfo.get("summary"),
-                "birthday": personinfo.get("birth_day"),
-                "gender": personinfo.get("gender")
-            })
+            return self._build_person_detail(personinfo)
         return None
 
+    @classmethod
+    def _build_person_detail(cls, personinfo: dict) -> schemas.MediaPerson:
+        """
+        构造Bangumi人物详情信息。
+        :param personinfo: Bangumi人物详情接口返回数据
+        :return: 媒体人物信息
+        """
+        return schemas.MediaPerson(source='bangumi', **{
+            "id": personinfo.get("id"),
+            "name": personinfo.get("name"),
+            "images": personinfo.get("images"),
+            "biography": personinfo.get("summary"),
+            "birthday": cls._normalize_optional_string(personinfo.get("birth_day")),
+            "gender": personinfo.get("gender")
+        })
+
+    @staticmethod
+    def _normalize_optional_string(value: object) -> Optional[str]:
+        """
+        规范化Bangumi接口中可能返回非字符串的可选文本字段。
+        :param value: 原始字段值
+        :return: 字符串字段值或None
+        """
+        if value is None:
+            return None
+        return str(value)
+
     def bangumi_person_credits(self, person_id: int) -> List[MediaInfo]:
         """
         根据TMDBID查询人物参演作品
diff --git a/tests/test_bangumi_module.py b/tests/test_bangumi_module.py
new file mode 100644
index 00000000..2d785cef
--- /dev/null
+++ b/tests/test_bangumi_module.py
@@ -0,0 +1,70 @@
+import asyncio
+
+from app.modules.bangumi import BangumiModule
+
+
+class _FakeBangumiApi:
+    """
+    测试用Bangumi API客户端。
+    """
+
+    def __init__(self, personinfo: dict):
+        """
+        初始化测试用人物详情数据。
+        :param personinfo: 人物详情接口返回数据
+        """
+        self.personinfo = personinfo
+
+    def person_detail(self, person_id: int) -> dict:
+        """
+        返回同步人物详情数据。
+        :param person_id: 人物ID
+        :return: 人物详情接口返回数据
+        """
+        return self.personinfo
+
+    async def async_person_detail(self, person_id: int) -> dict:
+        """
+        返回异步人物详情数据。
+        :param person_id: 人物ID
+        :return: 人物详情接口返回数据
+        """
+        return self.personinfo
+
+
+def test_bangumi_person_detail_normalizes_numeric_birthday():
+    """
+    Bangumi同步人物详情应兼容数字生日字段。
+    """
+    module = BangumiModule()
+    module.bangumiapi = _FakeBangumiApi({
+        "id": 1001,
+        "name": "测试人物",
+        "images": {"large": "https://example.com/person.jpg"},
+        "summary": "测试简介",
+        "birth_day": 22,
+        "gender": 1,
+    })
+
+    person = module.bangumi_person_detail(1001)
+
+    assert person.birthday == "22"
+
+
+def test_async_bangumi_person_detail_normalizes_numeric_birthday():
+    """
+    Bangumi异步人物详情应兼容数字生日字段。
+    """
+    module = BangumiModule()
+    module.bangumiapi = _FakeBangumiApi({
+        "id": 1002,
+        "name": "测试异步人物",
+        "images": {"large": "https://example.com/async-person.jpg"},
+        "summary": "测试异步简介",
+        "birth_day": 19,
+        "gender": 2,
+    })
+
+    person = asyncio.run(module.async_bangumi_person_detail(1002))
+
+    assert person.birthday == "19"