1. Click Tik Tok software to enter Tik Tok main interface and modify related settings. 2. Go to Tik Tok, click me, go to personal page, and then go to more pages. 3. Go to More Pages, click the Account and Security option, and then go to the Account and Security page. 4. Enter the account and security page, click the mobile phone binding, and modify the mobile phone number. 5. Then a prompt appears to change the bound mobile phone number. Click OK to go to the next page to change the mobile phone number.