diff --git a/extensions/memory-core/src/memory/qmd-manager.test.ts b/extensions/memory-core/src/memory/qmd-manager.test.ts
index 8781b28c1eb..fd94a391745 100644
--- a/extensions/memory-core/src/memory/qmd-manager.test.ts
+++ b/extensions/memory-core/src/memory/qmd-manager.test.ts
@@ -3822,6 +3822,40 @@ describe("QmdMemoryManager", () => {
     await manager.close();
   });
 
+  it("does not store qmd embed backoff when the process clock is invalid", async () => {
+    cfg = {
+      ...cfg,
+      memory: {
+        backend: "qmd",
+        qmd: {
+          includeDefaultMemory: false,
+          searchMode: "query",
+          update: {
+            interval: "0s",
+            debounceMs: 0,
+            onBoot: false,
+          },
+          paths: [{ path: workspaceDir, pattern: "**/*.md", name: "workspace" }],
+        },
+      },
+    } as OpenClawConfig;
+    const dateNowSpy = vi.spyOn(Date, "now").mockReturnValue(8_640_000_000_000_001);
+    const { manager } = await createManager({ mode: "status" });
+    try {
+      (
+        manager as unknown as {
+          noteEmbedFailure: (reason: string, err: unknown) => void;
+        }
+      ).noteEmbedFailure("manual", new Error("embed failed"));
+    } finally {
+      dateNowSpy.mockRestore();
+    }
+
+    const status = manager.status() as { custom?: { qmd?: { embedBackoffUntil?: number | null } } };
+    expect(status.custom?.qmd?.embedBackoffUntil).toBeNull();
+    await manager.close();
+  });
+
   it("runs periodic embed maintenance even when regular update scheduling is disabled", async () => {
     vi.useFakeTimers();
     cfg = {
diff --git a/extensions/memory-core/src/memory/qmd-manager.ts b/extensions/memory-core/src/memory/qmd-manager.ts
index 63da720ee10..a574c0d3b50 100644
--- a/extensions/memory-core/src/memory/qmd-manager.ts
+++ b/extensions/memory-core/src/memory/qmd-manager.ts
@@ -49,7 +49,11 @@ import {
   type ResolvedQmdConfig,
   type ResolvedQmdMcporterConfig,
 } from "openclaw/plugin-sdk/memory-core-host-engine-storage";
-import { addTimerTimeoutGraceMs } from "openclaw/plugin-sdk/number-runtime";
+import {
+  addTimerTimeoutGraceMs,
+  isFutureDateTimestampMs,
+  resolveExpiresAtMsFromDurationMs,
+} from "openclaw/plugin-sdk/number-runtime";
 import {
   localeLowercasePreservingWhitespace,
   normalizeLowercaseStringOrEmpty,
@@ -1701,7 +1705,7 @@ export class QmdMemoryManager implements MemorySearchManager {
       return false;
     }
     const now = Date.now();
-    if (this.embedBackoffUntil !== null && now < this.embedBackoffUntil) {
+    if (this.embedBackoffUntil !== null && isFutureDateTimestampMs(this.embedBackoffUntil)) {
       return false;
     }
     const embedIntervalMs = this.qmd.update.embedIntervalMs;
@@ -1808,7 +1812,7 @@ export class QmdMemoryManager implements MemorySearchManager {
       QMD_EMBED_BACKOFF_MAX_MS,
       QMD_EMBED_BACKOFF_BASE_MS * 2 ** Math.max(0, this.embedFailureCount - 1),
     );
-    this.embedBackoffUntil = Date.now() + delayMs;
+    this.embedBackoffUntil = resolveExpiresAtMsFromDurationMs(delayMs) ?? null;
     log.warn(
       `qmd embed failed (${reason}): ${String(err)}; backing off for ${Math.ceil(delayMs / 1000)}s`,
     );