You can change your password from the account settings page on the Dropbox website. You only need to make the change once and when you do, it will automatically apply to any computers or mobile devices linked to your account.
When using the Dropbox desktop application, you only need your password when you first install the Dropbox desktop application or whenever you link or relink your computer to your Dropbox account. Control all access to your Dropbox account via the Security tab of your account settings on the Dropbox website.
Dropbox for Business users: If you’re signed in to both a personal and work account at once, you’ll see a section in the Security tab for each account.
Enter your email address at the forgot password page on the Dropbox website. An email will be sent with a link you can use to reset your password.
If you've changed your password but are concerned about unauthorized access from a computer linked to your Dropbox account, consider using one of these security measures.