diff --git a/README.md b/README.md
index a465b20..10742a5 100644
--- a/README.md
+++ b/README.md
@@ -65,6 +65,8 @@ pip install yt-dlp
   * Inputs:
     * `url` (string, required): URL of the video
     * `resolution` (string, optional): Video resolution ('480p', '720p', '1080p', 'best'). Defaults to '720p'
+    * `startTime` (string, optional): Start time for trimming (format: HH:MM:SS[.ms]) - e.g., '00:01:30' or '00:01:30.500'
+    * `endTime` (string, optional): End time for trimming (format: HH:MM:SS[.ms]) - e.g., '00:02:45' or '00:02:45.500'
 
 * **download_audio**
   * Download audio in best available quality (usually m4a/mp3 format) to user's Downloads folder
diff --git a/docs/api.md b/docs/api.md
index 47a267a..25028ef 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -2,14 +2,16 @@
 
 ## Video Operations
 
-### downloadVideo(url: string, config?: Config, resolution?: string): Promise<string>
+### downloadVideo(url: string, config?: Config, resolution?: string, startTime?: string, endTime?: string): Promise<string>
 
-Downloads a video from the specified URL.
+Downloads a video from the specified URL with optional trimming.
 
 **Parameters:**
 - `url`: The URL of the video to download
 - `config`: (Optional) Configuration object
 - `resolution`: (Optional) Preferred video resolution ('480p', '720p', '1080p', 'best')
+- `startTime`: (Optional) Start time for trimming (format: HH:MM:SS[.ms])
+- `endTime`: (Optional) End time for trimming (format: HH:MM:SS[.ms])
 
 **Returns:**
 - Promise resolving to a success message with the downloaded file path
@@ -29,6 +31,26 @@ const hdResult = await downloadVideo(
   '1080p'
 );
 console.log(hdResult);
+
+// Download with trimming
+const trimmedResult = await downloadVideo(
+  'https://www.youtube.com/watch?v=jNQXAC9IVRw',
+  undefined,
+  '720p',
+  '00:01:30',
+  '00:02:45'
+);
+console.log(trimmedResult);
+
+// Download with fractional seconds
+const preciseTrim = await downloadVideo(
+  'https://www.youtube.com/watch?v=jNQXAC9IVRw',
+  undefined,
+  '720p',
+  '00:01:30.500',
+  '00:02:45.250'
+);
+console.log(preciseTrim);
 ```
 
 ## Audio Operations
diff --git a/src/__tests__/video.test.ts b/src/__tests__/video.test.ts
new file mode 100644
index 0000000..9a5badd
--- /dev/null
+++ b/src/__tests__/video.test.ts
@@ -0,0 +1,68 @@
+// @ts-nocheck
+// @jest-environment node
+import { describe, test, expect } from '@jest/globals';
+import * as os from 'os';
+import * as path from 'path';
+import { downloadVideo } from '../modules/video.js';
+import { CONFIG } from '../config.js';
+import * as fs from 'fs';
+
+// 設置 Python 環境
+process.env.PYTHONPATH = '';
+process.env.PYTHONHOME = '';
+
+describe('downloadVideo with trimming', () => {
+  const testUrl = 'https://www.youtube.com/watch?v=jNQXAC9IVRw';
+  const testConfig = {
+    ...CONFIG,
+    file: {
+      ...CONFIG.file,
+      downloadsDir: path.join(os.tmpdir(), 'yt-dlp-test-downloads'),
+      tempDirPrefix: 'yt-dlp-test-'
+    }
+  };
+
+  beforeEach(async () => {
+    await fs.promises.mkdir(testConfig.file.downloadsDir, { recursive: true });
+  });
+
+  afterEach(async () => {
+    await fs.promises.rm(testConfig.file.downloadsDir, { recursive: true, force: true });
+  });
+
+  test('downloads video with start time trimming', async () => {
+    const result = await downloadVideo(testUrl, testConfig, '720p', '00:00:10');
+    expect(result).toContain('Video successfully downloaded');
+    
+    const files = await fs.promises.readdir(testConfig.file.downloadsDir);
+    expect(files.length).toBeGreaterThan(0);
+    expect(files[0]).toMatch(/\.(mp4|webm|mkv)$/);
+  }, 30000);
+
+  test('downloads video with end time trimming', async () => {
+    const result = await downloadVideo(testUrl, testConfig, '720p', undefined, '00:00:20');
+    expect(result).toContain('Video successfully downloaded');
+    
+    const files = await fs.promises.readdir(testConfig.file.downloadsDir);
+    expect(files.length).toBeGreaterThan(0);
+    expect(files[0]).toMatch(/\.(mp4|webm|mkv)$/);
+  }, 30000);
+
+  test('downloads video with both start and end time trimming', async () => {
+    const result = await downloadVideo(testUrl, testConfig, '720p', '00:00:10', '00:00:20');
+    expect(result).toContain('Video successfully downloaded');
+    
+    const files = await fs.promises.readdir(testConfig.file.downloadsDir);
+    expect(files.length).toBeGreaterThan(0);
+    expect(files[0]).toMatch(/\.(mp4|webm|mkv)$/);
+  }, 30000);
+
+  test('downloads video without trimming when no times provided', async () => {
+    const result = await downloadVideo(testUrl, testConfig, '720p');
+    expect(result).toContain('Video successfully downloaded');
+    
+    const files = await fs.promises.readdir(testConfig.file.downloadsDir);
+    expect(files.length).toBeGreaterThan(0);
+    expect(files[0]).toMatch(/\.(mp4|webm|mkv)$/);
+  }, 30000);
+});
\ No newline at end of file
diff --git a/src/index.mts b/src/index.mts
index 6dbe2c6..1fa8c30 100644
--- a/src/index.mts
+++ b/src/index.mts
@@ -128,11 +128,19 @@ server.setRequestHandler(ListToolsRequestSchema, async () => {
           type: "object",
           properties: {
             url: { type: "string", description: "URL of the video" },
-            resolution: { 
-              type: "string", 
+            resolution: {
+              type: "string",
               description: "Preferred video resolution. For YouTube: '480p', '720p', '1080p', 'best'. For other platforms: '480p' for low quality, '720p'/'1080p' for HD, 'best' for highest quality. Defaults to '720p'",
               enum: ["480p", "720p", "1080p", "best"]
             },
+            startTime: {
+              type: "string",
+              description: "Start time for trimming (format: HH:MM:SS[.ms]) - e.g., '00:01:30' or '00:01:30.500'"
+            },
+            endTime: {
+              type: "string",
+              description: "End time for trimming (format: HH:MM:SS[.ms]) - e.g., '00:02:45' or '00:02:45.500'"
+            },
           },
           required: ["url"],
         },
@@ -197,10 +205,12 @@ server.setRequestHandler(
   CallToolRequestSchema,
   async (request: CallToolRequest) => {
     const toolName = request.params.name;
-    const args = request.params.arguments as { 
+    const args = request.params.arguments as {
       url: string;
       language?: string;
       resolution?: string;
+      startTime?: string;
+      endTime?: string;
     };
 
     if (toolName === "list_subtitle_languages") {
@@ -215,7 +225,13 @@ server.setRequestHandler(
       );
     } else if (toolName === "download_video") {
       return handleToolExecution(
-        () => downloadVideo(args.url, CONFIG, args.resolution as "480p" | "720p" | "1080p" | "best"),
+        () => downloadVideo(
+          args.url,
+          CONFIG,
+          args.resolution as "480p" | "720p" | "1080p" | "best",
+          args.startTime,
+          args.endTime
+        ),
         "Error downloading video"
       );
     } else if (toolName === "download_audio") {
diff --git a/src/modules/video.ts b/src/modules/video.ts
index a50db6b..3007deb 100644
--- a/src/modules/video.ts
+++ b/src/modules/video.ts
@@ -11,19 +11,21 @@ import {
 
 /**
  * Downloads a video from the specified URL.
- * 
+ *
  * @param url - The URL of the video to download
  * @param config - Configuration object for download settings
  * @param resolution - Preferred video resolution ('480p', '720p', '1080p', 'best')
+ * @param startTime - Optional start time for trimming (format: HH:MM:SS[.ms])
+ * @param endTime - Optional end time for trimming (format: HH:MM:SS[.ms])
  * @returns Promise resolving to a success message with the downloaded file path
  * @throws {Error} When URL is invalid or download fails
- * 
+ *
  * @example
  * ```typescript
  * // Download with default settings
  * const result = await downloadVideo('https://youtube.com/watch?v=...');
  * console.log(result);
- * 
+ *
  * // Download with specific resolution
  * const hdResult = await downloadVideo(
  *   'https://youtube.com/watch?v=...',
@@ -31,12 +33,24 @@ import {
  *   '1080p'
  * );
  * console.log(hdResult);
+ *
+ * // Download with trimming
+ * const trimmedResult = await downloadVideo(
+ *   'https://youtube.com/watch?v=...',
+ *   undefined,
+ *   '720p',
+ *   '00:01:30',
+ *   '00:02:45'
+ * );
+ * console.log(trimmedResult);
  * ```
  */
 export async function downloadVideo(
   url: string,
   config: Config,
-  resolution: "480p" | "720p" | "1080p" | "best" = "720p"
+  resolution: "480p" | "720p" | "1080p" | "best" = "720p",
+  startTime?: string,
+  endTime?: string
 ): Promise<string> {
   const userDownloadsDir = config.file.downloadsDir;
 
@@ -103,17 +117,36 @@ export async function downloadVideo(
       expectedFilename = randomFilename;
     }
 
+    // Build download arguments
+    const downloadArgs = [
+      "--ignore-config",
+      "--progress",
+      "--newline",
+      "--no-mtime",
+      "-f", format,
+      "--output", outputTemplate
+    ];
+
+    // Add trimming parameters if provided
+    if (startTime || endTime) {
+      let downloadSection = "*";
+      
+      if (startTime && endTime) {
+        downloadSection = `*${startTime}-${endTime}`;
+      } else if (startTime) {
+        downloadSection = `*${startTime}-`;
+      } else if (endTime) {
+        downloadSection = `*-${endTime}`;
+      }
+
+      downloadArgs.push("--download-sections", downloadSection, "--force-keyframes-at-cuts");
+    }
+
+    downloadArgs.push(url);
+
     // Download with progress info
     try {
-      await _spawnPromise("yt-dlp", [
-        "--ignore-config",
-        "--progress",
-        "--newline",
-        "--no-mtime",
-        "-f", format,
-        "--output", outputTemplate,
-        url
-      ]);
+      await _spawnPromise("yt-dlp", downloadArgs);
     } catch (error) {
       throw new Error(`Download failed: ${error instanceof Error ? error.message : String(error)}`);
     }