Court records show the actor filed his petition in Los Angeles yesterday, citing irreconcilable differences. Moore announced last year that she was ending her marriage to the actor 15 years her junior, but she never filed a petition.
Kutcher's filing does not indicate that the couple have a prenuptial agreement.
Kutcher and Moore (above) married in 2005 and kept their relationship very public, communicating with each other and fans on the social networking site Twitter.
After their break-up, Moore changed her name on the site from @mrskutcher to @justdemi.