diff --git a/src/auto-reply/reply/session.ts b/src/auto-reply/reply/session.ts
index 6c1b2233c0f..36131932bb4 100644
--- a/src/auto-reply/reply/session.ts
+++ b/src/auto-reply/reply/session.ts
@@ -5,7 +5,7 @@ import {
   normalizeConversationText,
   parseTelegramChatIdFromTarget,
 } from "../../acp/conversation-id.js";
-import { resolveSessionAgentId } from "../../agents/agent-scope.js";
+import { resolveAgentWorkspaceDir, resolveSessionAgentId } from "../../agents/agent-scope.js";
 import { clearBootstrapSnapshotOnSessionRollover } from "../../agents/bootstrap-cache.js";
 import { normalizeChatType } from "../../channels/chat-type.js";
 import type { OpenClawConfig } from "../../config/config.js";
@@ -30,6 +30,7 @@ import {
 } from "../../config/sessions.js";
 import type { TtsAutoMode } from "../../config/types.tts.js";
 import { archiveSessionTranscripts } from "../../gateway/session-utils.fs.js";
+import { createInternalHookEvent, triggerInternalHook } from "../../hooks/internal-hooks.js";
 import { resolveConversationIdFromTargets } from "../../infra/outbound/conversation-id.js";
 import { deliverSessionMaintenanceWarning } from "../../infra/session-maintenance-warning.js";
 import { createSubsystemLogger } from "../../logging/subsystem.js";
@@ -557,6 +558,26 @@ export async function initSessionState(params: {
     },
   );
 
+  // When a session is auto-reset (idle timeout or daily reset), emit a
+  // session:reset internal hook so the session-memory hook can persist
+  // the outgoing session context — just as it does for manual /new and /reset.
+  // Note: this is fire-and-forget; if archival renames the transcript before
+  // the handler reads it, getRecentSessionContentWithResetFallback() will
+  // locate it via the .reset.* sibling naming convention.
+  if (isNewSession && !resetTriggered && previousSessionEntry) {
+    const workspaceDir = resolveAgentWorkspaceDir(cfg, agentId);
+    const autoResetEvent = createInternalHookEvent("session", "reset", sessionKey, {
+      sessionEntry,
+      previousSessionEntry,
+      commandSource: "auto-reset",
+      workspaceDir,
+      cfg,
+    });
+    void triggerInternalHook(autoResetEvent).catch((err) => {
+      log.debug("session:reset hook error (auto-reset)", { error: String(err) });
+    });
+  }
+
   // Archive old transcript so it doesn't accumulate on disk (#14869).
   if (previousSessionEntry?.sessionId) {
     archiveSessionTranscripts({
diff --git a/src/hooks/bundled/session-memory/HOOK.md b/src/hooks/bundled/session-memory/HOOK.md
index c963e17b76c..f99070b43a8 100644
--- a/src/hooks/bundled/session-memory/HOOK.md
+++ b/src/hooks/bundled/session-memory/HOOK.md
@@ -1,13 +1,13 @@
 ---
 name: session-memory
-description: "Save session context to memory when /new or /reset command is issued"
+description: "Save session context to memory when session is reset (manual or automatic)"
 homepage: https://docs.openclaw.ai/automation/hooks#session-memory
 metadata:
   {
     "openclaw":
       {
         "emoji": "💾",
-        "events": ["command:new", "command:reset"],
+        "events": ["command:new", "command:reset", "session:reset"],
         "requires": { "config": ["workspace.dir"] },
         "install": [{ "id": "bundled", "kind": "bundled", "label": "Bundled with OpenClaw" }],
       },
@@ -16,11 +16,11 @@ metadata:
 
 # Session Memory Hook
 
-Automatically saves session context to your workspace memory when you issue `/new` or `/reset`.
+Automatically saves session context to your workspace memory when a session is reset, whether manually (`/new`, `/reset`) or automatically (idle timeout, daily reset).
 
 ## What It Does
 
-When you run `/new` or `/reset` to start a fresh session:
+When a session is reset (manually via `/new`/`/reset` or automatically via idle timeout or daily reset):
 
 1. **Finds the previous session** - Uses the pre-reset session entry to locate the correct transcript
 2. **Extracts conversation** - Reads the last N user/assistant messages from the session (default: 15, configurable)
diff --git a/src/hooks/bundled/session-memory/handler.ts b/src/hooks/bundled/session-memory/handler.ts
index 32fc36b23f0..d073ee5cc81 100644
--- a/src/hooks/bundled/session-memory/handler.ts
+++ b/src/hooks/bundled/session-memory/handler.ts
@@ -1,8 +1,10 @@
 /**
  * Session memory hook handler
  *
- * Saves session context to memory when /new or /reset command is triggered
- * Creates a new dated memory file with LLM-generated slug
+ * Saves session context to memory when a session is reset.
+ * Handles both manual resets (/new, /reset) and automatic resets
+ * (idle timeout, daily reset). Creates a new dated memory file
+ * with LLM-generated slug.
  */
 
 import fs from "node:fs/promises";
@@ -194,17 +196,22 @@ async function findPreviousSessionFile(params: {
 }
 
 /**
- * Save session context to memory when /new or /reset command is triggered
+ * Save session context to memory when session is reset.
+ *
+ * Triggers on:
+ * - command:new / command:reset  (manual /new or /reset commands)
+ * - session:reset                (automatic idle-timeout or daily resets)
  */
 const saveSessionToMemory: HookHandler = async (event) => {
-  // Only trigger on reset/new commands
-  const isResetCommand = event.action === "new" || event.action === "reset";
-  if (event.type !== "command" || !isResetCommand) {
+  const isManualReset =
+    event.type === "command" && (event.action === "new" || event.action === "reset");
+  const isAutoReset = event.type === "session" && event.action === "reset";
+  if (!isManualReset && !isAutoReset) {
     return;
   }
 
   try {
-    log.debug("Hook triggered for reset/new command", { action: event.action });
+    log.debug("Hook triggered for session reset", { type: event.type, action: event.action });
 
     const context = event.context || {};
     const cfg = context.cfg as OpenClawConfig | undefined;