diff --git a/apps/web/components/dev-task/DevTaskDetailDrawer.tsx b/apps/web/components/dev-task/DevTaskDetailDrawer.tsx
index ace120d..fba20da 100644
--- a/apps/web/components/dev-task/DevTaskDetailDrawer.tsx
+++ b/apps/web/components/dev-task/DevTaskDetailDrawer.tsx
@@ -1,14 +1,13 @@
 'use client';
 
 import { useState } from 'react';
-import { X, AlertTriangle, Link2, ChevronRight, Clock, User, Tag, Calendar } from 'lucide-react';
+import { X, AlertTriangle, Link2, ChevronRight, Clock, User, Tag, Calendar, Play } from 'lucide-react';
 import { StatusBadge } from './StatusBadge';
 import { CategoryChip } from './CategoryChip';
-import { WorklogPanel } from './WorklogPanel';
 import { useDevTaskStore } from '@/stores/useDevTaskStore';
 import { useTaskCategoryStore } from '@/stores/useTaskCategoryStore';
 import { useRequirementStore } from '@/stores/useRequirementStore';
-import { ALLOWED_TRANSITIONS, DEV_TASK_STATUS_LABEL, DEV_TASK_STATUS_COLOR, formatHours } from '@/lib/dev-task';
+import { ALLOWED_TRANSITIONS, DEV_TASK_STATUS_LABEL, DEV_TASK_STATUS_COLOR, formatHours, calcActualHoursByDates } from '@/lib/dev-task';
 import type { DevTaskStatus } from '@/lib/dev-task';
 
 interface Props {
@@ -153,8 +152,15 @@ export function DevTaskDetailDrawer({ taskId, allTaskIds, onClose }: Props) {
               <div className="flex items-center gap-2">
                 <Clock className="h-3 w-3 text-[var(--ink-muted)]" />
                 <span className="text-[var(--ink-muted)]">实际</span>
-                <span className="text-[var(--ink)] font-medium">{task.actualHours > 0 ? `${task.actualHours}h` : '-'}</span>
+                <span className="text-[var(--ink)] font-medium">{task.startDate ? formatHours(calcActualHoursByDates(task.startDate, task.completedAt)) : '-'}</span>
               </div>
+              {task.startDate && (
+                <div className="flex items-center gap-2">
+                  <Play className="h-3 w-3 text-[var(--ink-muted)]" />
+                  <span className="text-[var(--ink-muted)]">开始开发</span>
+                  <span className="text-[var(--ink)]">{task.startDate}</span>
+                </div>
+              )}
               {task.dueDate && (
                 <div className="flex items-center gap-2">
                   <Calendar className="h-3 w-3 text-[var(--ink-muted)]" />
@@ -194,10 +200,6 @@ export function DevTaskDetailDrawer({ taskId, allTaskIds, onClose }: Props) {
             </div>
           )}
 
-          {/* 卡片5：工时记录 */}
-          <div className="rounded-xl border border-[var(--line)] bg-[var(--bg-card)] p-4">
-            <WorklogPanel taskId={task.id} />
-          </div>
         </div>
       </div>
     </div>
diff --git a/apps/web/components/dev-task/DevTaskRow.tsx b/apps/web/components/dev-task/DevTaskRow.tsx
index 1006000..079769e 100644
--- a/apps/web/components/dev-task/DevTaskRow.tsx
+++ b/apps/web/components/dev-task/DevTaskRow.tsx
@@ -3,7 +3,7 @@
 import { AlertTriangle } from 'lucide-react';
 import { StatusBadge } from './StatusBadge';
 import { CategoryChip } from './CategoryChip';
-import { formatHours } from '@/lib/dev-task';
+import { formatHours, calcActualHoursByDates } from '@/lib/dev-task';
 import type { DevTask } from '@/lib/dev-task';
 import type { TaskCategory } from '@/lib/task-category';
 
@@ -39,8 +39,8 @@ export function DevTaskRow({ task, category, onClick }: Props) {
       <CategoryChip category={category} />
       <StatusBadge status={task.status} />
       <span className="text-[11px] text-[var(--ink-muted)] w-24 text-right tabular-nums">
-        {task.actualHours > 0 && <span className="text-[var(--ink-soft)]">{task.actualHours}h</span>}
-        {task.actualHours > 0 && ' / '}
+        {task.startDate && <span className="text-[var(--ink-soft)]">{calcActualHoursByDates(task.startDate, task.completedAt)}h</span>}
+        {task.startDate && ' / '}
         {formatHours(task.estimateHours).split('（')[0]}
       </span>
       <span className="text-[11px] text-[var(--ink-soft)] w-14 text-right truncate">{task.assigneeId}</span>
diff --git a/apps/web/lib/dev-task.ts b/apps/web/lib/dev-task.ts
index 729f285..eabe5f7 100644
--- a/apps/web/lib/dev-task.ts
+++ b/apps/web/lib/dev-task.ts
@@ -85,6 +85,22 @@ export function formatHours(hours: number): string {
   return `${hours}h（≈${days}人天）`;
 }
 
+export function calcActualHoursByDates(startDate?: string, completedAt?: string): number {
+  if (!startDate) return 0;
+  const end = completedAt || new Date().toISOString().slice(0, 10);
+  const start = new Date(startDate);
+  const endDate = new Date(end);
+  if (isNaN(start.getTime()) || isNaN(endDate.getTime()) || endDate < start) return 0;
+  let workDays = 0;
+  const current = new Date(start);
+  while (current <= endDate) {
+    const day = current.getDay();
+    if (day !== 0 && day !== 6) workDays++;
+    current.setDate(current.getDate() + 1);
+  }
+  return workDays * 8;
+}
+
 export function generateTaskNo(existingTasks: DevTask[]): string {
   const maxNum = existingTasks.reduce((max, t) => {
     const num = parseInt(t.taskNo.replace('DEV-', ''), 10);
diff --git a/apps/web/stores/useDevTaskStore.ts b/apps/web/stores/useDevTaskStore.ts
index 0488532..2c8d8db 100644
--- a/apps/web/stores/useDevTaskStore.ts
+++ b/apps/web/stores/useDevTaskStore.ts
@@ -77,8 +77,10 @@ export const useDevTaskStore = create<DevTaskState>((set, get) => ({
     if (!canTransition(task.status, to)) {
       return { ok: false, message: `不允许从「${task.status}」流转到「${to}」` };
     }
-    const completedAt = to === 'done' ? new Date().toISOString().slice(0, 10) : task.completedAt;
-    get().updateTask(id, { status: to, completedAt });
+    const today = new Date().toISOString().slice(0, 10);
+    const startDate = (to === 'in_progress' && !task.startDate) ? today : task.startDate;
+    const completedAt = to === 'done' ? today : task.completedAt;
+    get().updateTask(id, { status: to, startDate, completedAt });
     return { ok: true };
   },