It`s very simple , but before doing so please be aware that this will delete your Yahoo! ID, 360 blog, address book, Yahoo! Mail, Yahoo! Messenger ID, GeoCities website, My Yahoo, etc… It will remove everything and it’s not reversible so make sure you have a full copy of your address book, bookmarks, etc, before you apply to have your account cancelled.
Are you sure you want to delete your Yahoo! Account ? Your identity on Yahoo! ? Ok.. Click here and complete the form.