diff --git a/apps/api/src/services/incident_service.py b/apps/api/src/services/incident_service.py
index ee7af0ba..60bdb93c 100644
--- a/apps/api/src/services/incident_service.py
+++ b/apps/api/src/services/incident_service.py
@@ -163,8 +163,15 @@ def classify_alert_early(alertname: str, severity: str, labels: dict | None = No
     if severity in ("info", "none"):
         return "info", "TYPE-1"
 
-    # 5. Backup / Heartbeat（Velero 已由 K8s prefix 規則接管）
-    if "watchdog" in alertname_lower or alertname == "Heartbeat":
+    # 5. Backup / Heartbeat — 純資訊，不進 LLM
+    # HostBackupFailed 必須在 Host prefix 前攔截，否則被歸 host_resource/TYPE-3
+    # 2026-04-12 ogt: 補充 HostBackup/Backup/VeleroBackup 前綴
+    if (
+        "watchdog" in alertname_lower
+        or alertname == "Heartbeat"
+        or alertname.startswith(("HostBackup", "Backup", "VeleroBackup", "BackupRestore"))
+        or "backup" in alertname_lower
+    ):
         return "backup", "TYPE-1"
 
     # 6. 主機資源（從 infrastructure 分離，ADR-075 統帥決議）