diff --git a/extensions/feishu/src/media.test.ts b/extensions/feishu/src/media.test.ts
new file mode 100644
index 0000000000..433d193a1f
--- /dev/null
+++ b/extensions/feishu/src/media.test.ts
@@ -0,0 +1,151 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const createFeishuClientMock = vi.hoisted(() => vi.fn());
+const resolveFeishuAccountMock = vi.hoisted(() => vi.fn());
+const normalizeFeishuTargetMock = vi.hoisted(() => vi.fn());
+const resolveReceiveIdTypeMock = vi.hoisted(() => vi.fn());
+
+const fileCreateMock = vi.hoisted(() => vi.fn());
+const messageCreateMock = vi.hoisted(() => vi.fn());
+const messageReplyMock = vi.hoisted(() => vi.fn());
+
+vi.mock("./client.js", () => ({
+  createFeishuClient: createFeishuClientMock,
+}));
+
+vi.mock("./accounts.js", () => ({
+  resolveFeishuAccount: resolveFeishuAccountMock,
+}));
+
+vi.mock("./targets.js", () => ({
+  normalizeFeishuTarget: normalizeFeishuTargetMock,
+  resolveReceiveIdType: resolveReceiveIdTypeMock,
+}));
+
+import { sendMediaFeishu } from "./media.js";
+
+describe("sendMediaFeishu msg_type routing", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+
+    resolveFeishuAccountMock.mockReturnValue({
+      configured: true,
+      accountId: "main",
+      appId: "app_id",
+      appSecret: "app_secret",
+      domain: "feishu",
+    });
+
+    normalizeFeishuTargetMock.mockReturnValue("ou_target");
+    resolveReceiveIdTypeMock.mockReturnValue("open_id");
+
+    createFeishuClientMock.mockReturnValue({
+      im: {
+        file: {
+          create: fileCreateMock,
+        },
+        message: {
+          create: messageCreateMock,
+          reply: messageReplyMock,
+        },
+      },
+    });
+
+    fileCreateMock.mockResolvedValue({
+      code: 0,
+      data: { file_key: "file_key_1" },
+    });
+
+    messageCreateMock.mockResolvedValue({
+      code: 0,
+      data: { message_id: "msg_1" },
+    });
+
+    messageReplyMock.mockResolvedValue({
+      code: 0,
+      data: { message_id: "reply_1" },
+    });
+  });
+
+  it("uses msg_type=media for mp4", async () => {
+    await sendMediaFeishu({
+      cfg: {} as any,
+      to: "user:ou_target",
+      mediaBuffer: Buffer.from("video"),
+      fileName: "clip.mp4",
+    });
+
+    expect(fileCreateMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: expect.objectContaining({ file_type: "mp4" }),
+      }),
+    );
+
+    expect(messageCreateMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: expect.objectContaining({ msg_type: "media" }),
+      }),
+    );
+  });
+
+  it("uses msg_type=media for opus", async () => {
+    await sendMediaFeishu({
+      cfg: {} as any,
+      to: "user:ou_target",
+      mediaBuffer: Buffer.from("audio"),
+      fileName: "voice.opus",
+    });
+
+    expect(fileCreateMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: expect.objectContaining({ file_type: "opus" }),
+      }),
+    );
+
+    expect(messageCreateMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: expect.objectContaining({ msg_type: "media" }),
+      }),
+    );
+  });
+
+  it("uses msg_type=file for documents", async () => {
+    await sendMediaFeishu({
+      cfg: {} as any,
+      to: "user:ou_target",
+      mediaBuffer: Buffer.from("doc"),
+      fileName: "paper.pdf",
+    });
+
+    expect(fileCreateMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: expect.objectContaining({ file_type: "pdf" }),
+      }),
+    );
+
+    expect(messageCreateMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: expect.objectContaining({ msg_type: "file" }),
+      }),
+    );
+  });
+
+  it("uses msg_type=media when replying with mp4", async () => {
+    await sendMediaFeishu({
+      cfg: {} as any,
+      to: "user:ou_target",
+      mediaBuffer: Buffer.from("video"),
+      fileName: "reply.mp4",
+      replyToMessageId: "om_parent",
+    });
+
+    expect(messageReplyMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        path: { message_id: "om_parent" },
+        data: expect.objectContaining({ msg_type: "media" }),
+      }),
+    );
+
+    expect(messageCreateMock).not.toHaveBeenCalled();
+  });
+});