diff --git a/server/api/stats.py b/server/api/stats.py
index db7b3c4..d59a2cf 100644
--- a/server/api/stats.py
+++ b/server/api/stats.py
@@ -98,7 +98,7 @@ def stats_daily(request):
         replied = qs.filter(reply_status="已回复").count()
         wechat = qs.filter(wechat_exchanged=True).count()
         daily_data.append({
-            "date": day.isoformat(),
+            "date": f"{day.isoformat()}T00:00:00",
             "contacts": total,
             "replied": replied,
             "wechat": wechat,
diff --git a/server/api/tasks.py b/server/api/tasks.py
index f8921a4..c67c568 100644
--- a/server/api/tasks.py
+++ b/server/api/tasks.py
@@ -5,6 +5,7 @@
 """
 import json
 import logging
+from datetime import datetime
 
 from asgiref.sync import async_to_sync
 from rest_framework import status as http_status
@@ -20,6 +21,12 @@ from server.core.task_dispatcher import task_dispatcher
 logger = logging.getLogger("server.api.tasks")
 
 
+def _format_timestamp(ts: float) -> str:
+    """将时间戳转换为指定格式的字符串：2026-03-01T20:19:51"""
+    dt = datetime.fromtimestamp(ts)
+    return dt.strftime("%Y-%m-%dT%H:%M:%S")
+
+
 def _task_to_dict(t) -> dict:
     """将 TaskInfo 转为可序列化字典。"""
     return {
@@ -32,23 +39,49 @@ def _task_to_dict(t) -> dict:
         "progress": t.progress,
         "result": t.result,
         "error": t.error,
-        "created_at": t.created_at,
-        "updated_at": t.updated_at,
+        "created_at": _format_timestamp(t.created_at),
+        "updated_at": _format_timestamp(t.updated_at),
     }
 
 
 @api_view(["GET", "POST"])
 def task_list(request):
     """
-    GET  -> 查询任务列表，支持 ?worker_id= / ?status= / ?limit= 过滤
+    GET  -> 查询任务列表，支持以下过滤参数：
+           - ?worker_id=       : 按 Worker ID 过滤
+           - ?account_id=      : 按账号 ID 过滤（自动查询对应的 account_name）
+           - ?status=          : 按任务状态过滤
+           - ?limit=           : 返回条数上限，默认 50
     POST -> 提交新任务（支持 JSON 和 form-data）
     """
     if request.method == "GET":
         wid = request.query_params.get("worker_id")
+        account_id = request.query_params.get("account_id")
         st = request.query_params.get("status")
         limit = int(request.query_params.get("limit", 50))
         task_status = TaskStatus(st) if st else None
+        
+        # 如果指定了 account_id，先查询账号信息，转换为 account_name 过滤
+        account_name = None
+        if account_id:
+            try:
+                account_id = int(account_id)
+                account = BossAccount.objects.get(pk=account_id)
+                account_name = account.browser_name
+                if not wid:
+                    wid = account.worker_id
+            except (ValueError, BossAccount.DoesNotExist):
+                return api_error(
+                    http_status.HTTP_404_NOT_FOUND,
+                    f"未找到 id={account_id} 的账号",
+                )
+        
         tasks = task_dispatcher.list_tasks(worker_id=wid, status=task_status, limit=limit)
+        
+        # 按 account_name 进一步过滤（如果指定了 account_id）
+        if account_name:
+            tasks = [t for t in tasks if t.account_name == account_name]
+        
         return api_success([_task_to_dict(t) for t in tasks])
 
     # POST: 提交新任务
diff --git a/server/serializers.py b/server/serializers.py
index dec0c1f..5d5c86f 100644
--- a/server/serializers.py
+++ b/server/serializers.py
@@ -56,8 +56,8 @@ class TaskOutSerializer(serializers.Serializer):
     progress = serializers.CharField(allow_null=True)
     result = serializers.JSONField(allow_null=True)
     error = serializers.CharField(allow_null=True)
-    created_at = serializers.FloatField()
-    updated_at = serializers.FloatField()
+    created_at = serializers.CharField()
+    updated_at = serializers.CharField()
 
 
 # ────────────────────────── Worker ──────────────────────────
diff --git a/server/settings.py b/server/settings.py
index 0f64ba1..54af651 100644
--- a/server/settings.py
+++ b/server/settings.py
@@ -68,6 +68,7 @@ REST_FRAMEWORK = {
         "rest_framework.parsers.MultiPartParser",
     ],
     "EXCEPTION_HANDLER": "server.core.exception_handler.custom_exception_handler",
+    "DATETIME_FORMAT": "%Y-%m-%dT%H:%M:%S",
 }
 
 # ─── Channels ───