diff --git a/routes/edm_routes.py b/routes/edm_routes.py
index ce2ad5d..b8c49fb 100644
--- a/routes/edm_routes.py
+++ b/routes/edm_routes.py
@@ -7,12 +7,15 @@ EDM 與節慶促銷路由模組
 
 import hashlib
 import math
+import os
+import pickle
 from datetime import datetime, timezone, timedelta
+from pathlib import Path
 from flask import Blueprint, request, render_template, url_for
 from auth import login_required
 from sqlalchemy import func, desc
 
-from config import BASE_DIR, public_url, DATABASE_TYPE
+from config import BASE_DIR, public_url, DATABASE_TYPE, SYSTEM_VERSION
 from database.manager import DatabaseManager
 from database.models import Product
 from database.edm_models import PromoProduct
@@ -32,6 +35,7 @@ _PROMO_DASHBOARD_CACHE = {}
 _PROMO_DASHBOARD_CACHE_MAX = 32
 _PROMO_PAGE_SIZE_DEFAULT = 24
 _PROMO_PAGE_SIZE_MAX = 200
+_PROMO_SHARED_CACHE_FILE = Path(BASE_DIR) / 'data' / 'promo_dashboard_cache.pkl'
 
 
 # ==========================================
@@ -103,6 +107,52 @@ def _remember_promo_dashboard_data(cache_key, data):
     _PROMO_DASHBOARD_CACHE[cache_key] = data
 
 
+def _load_shared_promo_dashboard_cache(cache_key):
+    """讀取跨 worker 促銷 dashboard 快取，讓冷 worker 不必重算首屏資料。"""
+    try:
+        if not os.path.exists(_PROMO_SHARED_CACHE_FILE):
+            return None
+        with open(_PROMO_SHARED_CACHE_FILE, 'rb') as f:
+            payload = pickle.load(f)
+        if payload.get('version') != SYSTEM_VERSION:
+            return None
+        entries = payload.get('entries')
+        if not isinstance(entries, dict):
+            return None
+        return entries.get(cache_key)
+    except Exception:
+        sys_log.debug("promo dashboard shared cache load failed", exc_info=True)
+        return None
+
+
+def _write_shared_promo_dashboard_cache(cache_key, data):
+    """原子寫入促銷 dashboard 共享快取；失敗不阻斷頁面回應。"""
+    cache_file = str(_PROMO_SHARED_CACHE_FILE)
+    tmp_file = f"{cache_file}.{os.getpid()}.tmp"
+    entries = {}
+    try:
+        if os.path.exists(_PROMO_SHARED_CACHE_FILE):
+            with open(_PROMO_SHARED_CACHE_FILE, 'rb') as f:
+                payload = pickle.load(f)
+            if payload.get('version') == SYSTEM_VERSION and isinstance(payload.get('entries'), dict):
+                entries = payload['entries']
+        entries[cache_key] = data
+        while len(entries) > _PROMO_DASHBOARD_CACHE_MAX:
+            entries.pop(next(iter(entries)))
+
+        os.makedirs(os.path.dirname(cache_file), exist_ok=True)
+        with open(tmp_file, 'wb') as f:
+            pickle.dump({'version': SYSTEM_VERSION, 'entries': entries}, f, protocol=pickle.HIGHEST_PROTOCOL)
+        os.replace(tmp_file, cache_file)
+    except Exception:
+        try:
+            if os.path.exists(tmp_file):
+                os.remove(tmp_file)
+        except OSError:
+            pass
+        sys_log.debug("promo dashboard shared cache write failed", exc_info=True)
+
+
 def _get_promo_page_window_args():
     """讀取促銷商品清單分頁參數，限制首屏 HTML 重量。"""
     page = request.args.get('page', 1, type=int) or 1
@@ -142,6 +192,10 @@ def _build_promo_dashboard_data(session, page_type, page_name, sort_by, order, r
     cached_data = _PROMO_DASHBOARD_CACHE.get(cache_key)
     if cached_data is not None:
         return cached_data
+    cached_data = _load_shared_promo_dashboard_cache(cache_key)
+    if cached_data is not None:
+        _remember_promo_dashboard_data(cache_key, cached_data)
+        return cached_data
 
     # 1. 基礎統計
     last_update = session.query(PromoProduct.crawled_at).filter(
@@ -374,6 +428,7 @@ def _build_promo_dashboard_data(session, page_type, page_name, sort_by, order, r
         'current_batch_id': current_batch_id
     }
     _remember_promo_dashboard_data(cache_key, data)
+    _write_shared_promo_dashboard_cache(cache_key, data)
     return data
 
 
diff --git a/tests/test_cache_manager.py b/tests/test_cache_manager.py
index 177a62d..f12992e 100644
--- a/tests/test_cache_manager.py
+++ b/tests/test_cache_manager.py
@@ -1,4 +1,5 @@
 from pathlib import Path
+import pickle
 from flask import Flask, session
 
 
@@ -182,6 +183,46 @@ def test_clear_daily_sales_cache_removes_shared_view_cache_files(tmp_path, monke
     assert not cache_file.exists()
 
 
+def test_promo_dashboard_shared_cache_roundtrip(tmp_path, monkeypatch):
+    from routes import edm_routes
+
+    shared_cache = tmp_path / "promo_dashboard_cache.pkl"
+    monkeypatch.setattr(edm_routes, "_PROMO_SHARED_CACHE_FILE", shared_cache)
+    edm_routes._PROMO_DASHBOARD_CACHE.clear()
+    cache_key = ("edm", "default", "desc", "", "2026-05-19-12", (10, "2026-05-19T12:00:00", 30))
+    data = {
+        "sorted_grouped_items": {"11:00": []},
+        "slot_stats": {"11:00": {"on_shelf": 0}},
+        "items_in_batch": [],
+        "last_update_str": "2026-05-19 12:00",
+        "activity_time": "11:00",
+        "active_tab": "11:00",
+        "current_batch_id": "batch-1",
+    }
+
+    edm_routes._write_shared_promo_dashboard_cache(cache_key, data)
+    edm_routes._PROMO_DASHBOARD_CACHE.clear()
+
+    assert edm_routes._load_shared_promo_dashboard_cache(cache_key) == data
+    assert shared_cache.exists()
+
+
+def test_promo_dashboard_shared_cache_ignores_other_versions(tmp_path, monkeypatch):
+    from routes import edm_routes
+
+    shared_cache = tmp_path / "promo_dashboard_cache.pkl"
+    cache_key = ("edm", "default", "desc", "", "bucket", (1, "ts", 1))
+    shared_cache.write_bytes(
+        pickle.dumps(
+            {"version": "older-version", "entries": {cache_key: {"stale": True}}},
+            protocol=pickle.HIGHEST_PROTOCOL,
+        )
+    )
+    monkeypatch.setattr(edm_routes, "_PROMO_SHARED_CACHE_FILE", shared_cache)
+
+    assert edm_routes._load_shared_promo_dashboard_cache(cache_key) is None
+
+
 def test_sales_analysis_preview_context_cache_avoids_reloading_options(tmp_path, monkeypatch):
     from routes import sales_routes
 
diff --git a/tests/test_frontend_v2_assets.py b/tests/test_frontend_v2_assets.py
index c3b6cad..c2acf93 100644
--- a/tests/test_frontend_v2_assets.py
+++ b/tests/test_frontend_v2_assets.py
@@ -423,9 +423,10 @@ def test_ai_product_pick_agent_uses_real_competitor_data_and_dashboard_action():
 def test_edm_dashboard_v2_is_production_default_and_uses_real_campaign_data():
     route_source = (ROOT / "routes/edm_routes.py").read_text(encoding="utf-8")
     template = (ROOT / "templates/edm_dashboard_v2.html").read_text(encoding="utf-8")
+    page_js = (ROOT / "web/static/js/page-edm-v2.js").read_text(encoding="utf-8")
 
-    assert route_source.count("request.args.get('ui') == 'legacy'") == 5
-    assert "template_name = 'edm_dashboard.html' if request.args.get('ui') == 'legacy' else 'edm_dashboard_v2.html'" in route_source
+    assert "request.args.get('ui') == 'legacy'" not in route_source
+    assert route_source.count("template_name = 'edm_dashboard_v2.html'") == 5
     assert "{% for slot, stats in slot_stats.items() %}" in template
     assert "{% for item in items %}" in template
     assert "scheduler_stats.get(task_key, [])" in template
@@ -435,13 +436,13 @@ def test_edm_dashboard_v2_is_production_default_and_uses_real_campaign_data():
     assert "data-campaign-filter=\"down\"" in template
     assert "data-campaign-filter=\"delisted\"" in template
     assert "data-campaign-history-trigger" in template
-    assert "showCampaignHistory(this.dataset.iCode, this.dataset.productName)" in template
-    assert "fetch(`/api/history/i-code/${encodeURIComponent(iCode)}?range=${activeCampaignHistoryRange}`)" in template
+    assert "showCampaignHistory(button.dataset.iCode, button.dataset.productName)" in page_js
+    assert "fetch(`/api/history/i-code/${encodeURIComponent(iCode)}?range=${activeCampaignHistoryRange}`)" in page_js
     assert "data-campaign-history-range=\"week\"" in template
     assert "data-campaign-history-range=\"month\"" in template
     assert "data-campaign-history-range=\"quarter\"" in template
     assert "data-campaign-history-range=\"year\"" in template
-    assert "applyCampaignFilter(card, button.dataset.campaignFilter)" in template
+    assert "applyCampaignFilter(card, button.dataset.campaignFilter)" in page_js
     assert "?ui=v2" not in template
     assert "ui='v2'" not in template
     assert "mock" not in template.lower()