diff --git a/backend/src/main/java/com/designhub/service/TaskApprovalService.java b/backend/src/main/java/com/designhub/service/TaskApprovalService.java
index 9fe1e89..463644a 100644
--- a/backend/src/main/java/com/designhub/service/TaskApprovalService.java
+++ b/backend/src/main/java/com/designhub/service/TaskApprovalService.java
@@ -226,8 +226,19 @@ public class TaskApprovalService {
             // 普通任务：根据是否指定接收人设置状态
             if (assignedReceiverId != null) {
                 task.setStatus("in_progress"); // 指定接单直接进入进行中状态
-                task.setStartTime(LocalDateTime.now());
-                task.setActualStartTime(LocalDateTime.now());
+                LocalDateTime now = LocalDateTime.now();
+                task.setStartTime(now);
+                task.setActualStartTime(now);
+                
+                // 重新计算deadline：从指定接单时间开始计算
+                if (task.getEstimatedHours() != null) {
+                    int hours = task.getEstimatedHours().intValue();
+                    if (hours > 0) {
+                        task.setDeadline(now.plusHours(hours));
+                        log.info("任务deadline已重新计算：从指定接单时间 {} 开始，预估 {} 小时，截止时间 {}", 
+                                now, hours, task.getDeadline());
+                    }
+                }
             } else {
                 task.setStatus("pending"); // 未指定则发布到大厅
             }
diff --git a/backend/src/main/java/com/designhub/service/TaskService.java b/backend/src/main/java/com/designhub/service/TaskService.java
index ea405bc..10bbcdc 100644
--- a/backend/src/main/java/com/designhub/service/TaskService.java
+++ b/backend/src/main/java/com/designhub/service/TaskService.java
@@ -767,11 +767,14 @@ public class TaskService {
         }
         
         LocalDateTime now = LocalDateTime.now();
-        LocalDateTime deadline = task.getDeadline();
-        if (deadline == null && task.getEstimatedHours() != null) {
+        // 重新计算deadline：从接单时间开始计算，无论之前是否有deadline
+        LocalDateTime deadline = null;
+        if (task.getEstimatedHours() != null) {
             int hours = task.getEstimatedHours().intValue();
             if (hours > 0) {
                 deadline = now.plusHours(hours);
+                log.info("任务deadline已重新计算：从接单时间 {} 开始，预估 {} 小时，截止时间 {}", 
+                        now, hours, deadline);
             }
         }