The former "Will and Grace" star filed her petition in Los Angeles on Tuesday, citing irreconcilable differences.
Messing married Daniel Zelman, a writer and executive producer of the show "Damages," in September 2000, but the couple separated in February 2010.
They have an 8-year-old son and she is seeking joint custody. Her petition requests that Zelman pay her attorney fees and spousal support.
Messing currently appears on the NBC series "Smash."
The filing was first reported by celebrity website TMZ.