1. Open Tik Tok and enter the main page. Find the "I" button in the lower right corner and click to enter the personal page.

2. On the personal page, find the video that needs to change music, and click to enter the video.

3. On the video page, click the ellipsis on the right to enter the hidden interface, and select "Save to Local".

4. Return to the personal page and click the plus button at the bottom of the screen to enter the shooting page. Click on the photo album to import the locally saved video into Tik Tok.

5. After importing the video, click Next, and then click "Select Music".

6. In the music selection interface, click the "Volume" option to modulate the original sound to 0. Select the new music you want to add as an audio track.

7. After completing the music selection, save the released works, and the new music will replace the original music.