diff --git a/CHANGELOG.md b/CHANGELOG.md
index 71f7bfc4bcc..5decd90e643 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -35,6 +35,7 @@ Docs: https://docs.openclaw.ai
 - Providers/configure: preserve the existing default model when adding or reauthing a provider whose plugin returns a default-model config patch. Fixes #50268. Thanks @rixcorp-oc.
 - Slack/message actions: send media before the follow-up Block Kit message when Slack `send` includes a file plus presentation or interactive controls, so file attachments are no longer rejected. Fixes #51458. Thanks @HirokiKobayashi-R.
 - Slack/DMs: honor `dmHistoryLimit` for fresh 1:1 Slack DM sessions by backfilling recent conversation history before the current reply. Fixes #64427. Thanks @brantley-creator.
+- Slack/DMs: keep top-level direct messages on the stable DM session even when `replyToMode` targets Slack thread replies, preserving context across DM turns. Fixes #58832. Thanks @daye-jjeong.
 - Slack/mentions: resolve `<!subteam^...>` user-group mentions through Slack `usergroups.users.list` and treat them as explicit mentions only when the bot user is a member, so mention-gated agent channels wake for real user-group mentions without config-only allowlists. Fixes #73827. Thanks @CG-Intelligence-Agent-Jack.
 - Slack/message tool: let `read` fetch an exact Slack message timestamp, including a specific thread reply when paired with `threadId`, instead of returning only the parent thread or recent channel history. Fixes #53943. Thanks @zomars.
 - Web search: point missing-key errors to `web_fetch` for known URLs and the browser tool for interactive pages. Thanks @zhaoyang97.
diff --git a/extensions/slack/src/monitor/message-handler/prepare-routing.ts b/extensions/slack/src/monitor/message-handler/prepare-routing.ts
index 15aed81c391..4eede47b79b 100644
--- a/extensions/slack/src/monitor/message-handler/prepare-routing.ts
+++ b/extensions/slack/src/monitor/message-handler/prepare-routing.ts
@@ -92,9 +92,9 @@ export function resolveSlackRoutingContext(params: {
   const threadContext = resolveSlackThreadContext({ message, replyToMode });
   const threadTs = threadContext.incomingThreadTs;
   const isThreadReply = threadContext.isThreadReply;
-  // Keep true thread replies thread-scoped, but preserve channel-level sessions
-  // for top-level room turns when replyToMode is off.
-  // For DMs, preserve existing auto-thread behavior when replyToMode="all".
+  // Keep true thread replies thread-scoped, while top-level DMs keep their
+  // stable direct-message session even when reply delivery targets a Slack UI
+  // thread.
   const autoThreadId =
     !isThreadReply && replyToMode === "all" && threadContext.messageTs
       ? threadContext.messageTs
@@ -115,7 +115,15 @@ export function resolveSlackRoutingContext(params: {
       ? seedCandidateThreadId
       : undefined;
   const roomThreadId = isThreadReply && threadTs ? threadTs : undefined;
-  const canonicalThreadId = isRoomish ? roomThreadId : isThreadReply ? threadTs : autoThreadId;
+  const canonicalThreadId = isDirectMessage
+    ? isThreadReply
+      ? threadTs
+      : undefined
+    : isRoomish
+      ? roomThreadId
+      : isThreadReply
+        ? threadTs
+        : autoThreadId;
   const routedThreadId = canonicalThreadId ?? (isRoomish ? seededRoomThreadId : undefined);
   const baseConversationId = resolveSlackBaseConversationId({ message, isDirectMessage });
   const boundThreadRoute = routedThreadId
diff --git a/extensions/slack/src/monitor/message-handler/prepare.test.ts b/extensions/slack/src/monitor/message-handler/prepare.test.ts
index 70c507a6b40..52c1215458a 100644
--- a/extensions/slack/src/monitor/message-handler/prepare.test.ts
+++ b/extensions/slack/src/monitor/message-handler/prepare.test.ts
@@ -1073,11 +1073,11 @@ describe("slack prepareSlackMessage inbound contract", () => {
     expect(prepared!.ctxPayload.Body).not.toContain("parent_user_id");
   });
 
-  it("creates thread session for top-level DM when replyToMode=all", async () => {
+  it("keeps top-level DM session stable when replyToMode=all", async () => {
     const { storePath } = storeFixture.makeTmpStorePath();
     const slackCtx = createInboundSlackCtx({
       cfg: {
-        session: { store: storePath },
+        session: { store: storePath, dmScope: "per-channel-peer" },
         channels: { slack: { enabled: true, replyToMode: "all" } },
       } as OpenClawConfig,
       replyToMode: "all",
@@ -1092,9 +1092,7 @@ describe("slack prepareSlackMessage inbound contract", () => {
     );
 
     expect(prepared).toBeTruthy();
-    // Session key should include :thread:500.000 for the auto-threaded message
-    expect(prepared!.ctxPayload.SessionKey).toContain(":thread:500.000");
-    // MessageThreadId should be set for the reply
+    expect(prepared!.ctxPayload.SessionKey).toBe("agent:main:slack:direct:u1");
     expect(prepared!.ctxPayload.MessageThreadId).toBe("500.000");
   });
 
diff --git a/extensions/slack/src/monitor/message-handler/prepare.thread-session-key.test.ts b/extensions/slack/src/monitor/message-handler/prepare.thread-session-key.test.ts
index 0a7f39cb358..fb55c3a6eda 100644
--- a/extensions/slack/src/monitor/message-handler/prepare.thread-session-key.test.ts
+++ b/extensions/slack/src/monitor/message-handler/prepare.thread-session-key.test.ts
@@ -4,10 +4,14 @@ import type { ResolvedSlackAccount } from "../../accounts.js";
 import type { SlackMessageEvent } from "../../types.js";
 import { resolveSlackRoutingContext, type SlackRoutingContextDeps } from "./prepare-routing.js";
 
-function buildCtx(overrides?: { replyToMode?: "all" | "first" | "off" | "batched" }) {
+function buildCtx(overrides?: {
+  replyToMode?: "all" | "first" | "off" | "batched";
+  dmScope?: "main" | "per-sender" | "per-channel-peer";
+}) {
   const replyToMode = overrides?.replyToMode ?? "all";
   return {
     cfg: {
+      session: { dmScope: overrides?.dmScope },
       channels: {
         slack: { enabled: true, replyToMode },
       },
@@ -321,4 +325,28 @@ describe("thread-level session keys", () => {
     const sessionKey = routing.sessionKey;
     expect(sessionKey).not.toContain(":thread:");
   });
+
+  it("keeps top-level DMs on the direct session when replyToMode=all", () => {
+    const ctx = buildCtx({ replyToMode: "all", dmScope: "per-channel-peer" });
+    const account = buildAccount("all");
+
+    const routing = resolveSlackRoutingContext({
+      ctx,
+      account,
+      message: {
+        channel: "D456",
+        channel_type: "im",
+        user: "U3",
+        text: "dm message",
+        ts: "1770408530.000000",
+      } as SlackMessageEvent,
+      isDirectMessage: true,
+      isGroupDm: false,
+      isRoom: false,
+      isRoomish: false,
+    });
+
+    expect(routing.sessionKey).toBe("agent:main:slack:direct:u3");
+    expect(routing.threadContext.messageThreadId).toBe("1770408530.000000");
+  });
 });