diff --git a/api/api_v1/endpoints/query.py b/api/api_v1/endpoints/query.py
index 1d5d0b4..97f4670 100644
--- a/api/api_v1/endpoints/query.py
+++ b/api/api_v1/endpoints/query.py
@@ -261,8 +261,11 @@ async def event_model(
             for group, df_group in df.groupby(groupby):
                 #在原数据上将索引重新转换为列，新索引的列删除
                 df_group.reset_index(drop=True, inplace=True)
-                q['groups'].append(str(group))
-
+                #判断为0的改成未知城市
+                if str(group) == '0' and analysis.event_view['groupBy'][0]['columnDesc']== '城市':
+                    q['groups'].append('未知城市')
+                else:
+                    q['groups'].append(str(group))
                 concat_data = []
                 for i in set(date_range) - set(df_group['date']):
                     if len(groupby) > 1: