diff --git a/.gitea/workflows/pr-automation.yml b/.gitea/workflows/pr-automation.yml
index 663576e21..b8606dffb 100755
--- a/.gitea/workflows/pr-automation.yml
+++ b/.gitea/workflows/pr-automation.yml
@@ -5,6 +5,10 @@ on:
     types: [synchronize, opened, ready_for_review, review_requested]
   workflow_dispatch:
 
+concurrency:
+  group: pr-automation-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: read
 
@@ -13,7 +17,7 @@ jobs:
     name: Auto Approve on CI Green
     runs-on: ci-check
     if: github.event_name == 'pull_request' && !github.event.pull_request.draft
-    timeout-minutes: 3  # 长等待模式：等CI全绿后自动合并，不遗漏任何PR
+    timeout-minutes: 3  # 短作业模式：快速判断后退出，靠pr-auto-scan兜底
     steps:
       - name: Checkout code
         shell: sh
@@ -56,7 +60,7 @@ jobs:
     name: Auto Merge on CI Green + Approved
     runs-on: ci-check
     if: github.event_name == 'pull_request' && !github.event.pull_request.draft && github.event.pull_request.base.ref == 'develop'
-    timeout-minutes: 45  # 长等待模式：等CI全绿后自动合并，不遗漏任何PR
+    timeout-minutes: 2  # 短作业模式：快速判断后退出，靠pr-auto-scan每5分钟兜底
     steps:
       - name: Checkout code
         shell: sh
diff --git a/scripts/ci/auto_merge.sh b/scripts/ci/auto_merge.sh
index acb8dcdef..d5adc19a0 100644
--- a/scripts/ci/auto_merge.sh
+++ b/scripts/ci/auto_merge.sh
@@ -31,15 +31,15 @@ echo "检查CI Gate统一门禁"
 echo
 
 # 初始等待30秒，给CI启动写status的时间
-echo "等待30秒让CI启动..."
-sleep 30
+echo "等待15秒让CI启动..."
+sleep 15
 
 # 405连续计数器
 MERGE_405_COUNT=0
-MAX_405_RETRIES=10
+MAX_405_RETRIES=2
 
 # 轮询等待，最多30分钟（180次x10秒）
-for attempt in $(seq 1 90); do  # 最多等45分钟(90次x30秒)，确保等得到Worker构建完成
+for attempt in $(seq 1 2); do  # 短作业模式：检查2次就退出，靠pr-auto-scan每5分钟兜底
   ALL_SUCCESS=true
   ANY_FAILED=false
   ANY_PENDING=false
@@ -106,7 +106,7 @@ for attempt in $(seq 1 90); do  # 最多等45分钟(90次x30秒)，确保等得
           "${GITHUB_API_URL}/repos/${GITHUB_REPOSITORY}/issues/${PR_NUMBER}/comments" > /dev/null 2>&1 || true
         exit 0
       fi
-      sleep 30
+      sleep 15
       continue
     else
       echo "自动合并失败 (HTTP $HTTP_CODE)"
@@ -129,9 +129,9 @@ for attempt in $(seq 1 90); do  # 最多等45分钟(90次x30秒)，确保等得
     exit 0
   fi
 
-  sleep 30
+  sleep 15
 done
 
 echo
-echo "快速检查超时（3分钟），CI尚未全绿或无审批，退出等待下次触发"
+echo "短作业检查完成（CI尚未全绿），CI尚未全绿或无审批，退出等待下次触发"
 exit 0