How to remove your IMDb account
Be logged in and use the removal link. What will be removed, apart from your account information: ‘your vote history and My Movies information. This cannot be reversed so please be sure that you really want to do this.’
Direct removal link: https://secure.imdb.com/register-imdb/delete
Helpful Trick: Removing online data
Helpful Trick: Remove third-party logins
If you signed up for IMDb using a third-party login such as Facebook or Twitter, you probably want to revoke all access from IMDb. Click here to find out how.