diff --git a/backend/api/routes/trades.py b/backend/api/routes/trades.py
index d655483..9d9b60c 100644
--- a/backend/api/routes/trades.py
+++ b/backend/api/routes/trades.py
@@ -30,18 +30,28 @@ def get_date_range(period: Optional[str] = None):
     Returns:
         (start_date, end_date) 元组，格式为 'YYYY-MM-DD HH:MM:SS'
     """
+    # 使用当前时间作为结束时间，确保包含最新的单子
     end_date = datetime.now()
     
     if period == '1d':
-        start_date = end_date - timedelta(days=1)
+        # 最近1天：从今天00:00:00到现在（确保包含今天的所有单子）
+        # 这样即使查询时已经是晚上，也能查到今天早上开的单子
+        start_date = end_date.replace(hour=0, minute=0, second=0, microsecond=0)
     elif period == '7d':
-        start_date = end_date - timedelta(days=7)
+        # 最近7天：从7天前00:00:00到现在
+        start_date = (end_date - timedelta(days=7)).replace(hour=0, minute=0, second=0, microsecond=0)
     elif period == '30d':
-        start_date = end_date - timedelta(days=30)
+        # 最近30天：从30天前00:00:00到现在
+        start_date = (end_date - timedelta(days=30)).replace(hour=0, minute=0, second=0, microsecond=0)
     else:
         return None, None
     
-    return start_date.strftime('%Y-%m-%d 00:00:00'), end_date.strftime('%Y-%m-%d %H:%M:%S')
+    # 开始时间：使用计算出的开始日期的00:00:00
+    start_date_str = start_date.strftime('%Y-%m-%d %H:%M:%S')
+    # 结束时间：使用当前时间，确保包含最新单子
+    end_date_str = end_date.strftime('%Y-%m-%d %H:%M:%S')
+    
+    return start_date_str, end_date_str
 
 
 @router.get("")