diff --git a/backend/app/api/kpis.py b/backend/app/api/kpis.py
index aae03b3b..61f203b6 100644
--- a/backend/app/api/kpis.py
+++ b/backend/app/api/kpis.py
@@ -482,7 +482,25 @@ def get_kpi(kpi_id: int, db: Session = Depends(get_db), entity_id: int = Depends
     # 账套隔离: 禁止跨企业读取 (2026-08-23 P1a)
     if kpi.entity_id != entity_id:
         raise HTTPException(404, "KPI不存在")
-    return kpi_to_dict(kpi)
+    result = kpi_to_dict(kpi)
+    # 附带历史数据（前端KPI详情"历史数据"Tab依赖）
+    # 2026-08-26修复: 原实现只返回定义信息，values缺失导致历史数据Tab空白
+    vals = db.query(KPIValue).filter(
+        KPIValue.kpi_id == kpi_id,
+        KPIValue.actual_value.isnot(None),
+    ).order_by(KPIValue.period.asc()).all()
+    result["values"] = [
+        {
+            "id": v.id,
+            "period": v.period,
+            "actual_value": v.actual_value,
+            "source_type": v.source_type,
+            "data_status": v.data_status,
+            "source_batch": v.source_batch,
+        }
+        for v in vals
+    ]
+    return result
 
 
 def _validate_kpi_data(data: dict, db: Session, current_kpi_id: Optional[int] = None, is_update: bool = False):