The third time just wasn't the charm.
Donatacci, 41, a former Playboy model, is citing irreconcilable differences as the cause for the split , according to the mag.
The "Frasier" star and Donatacci have been married since Aug. 1997 and have two children together, daughter Mason, 8, and son Jude, 5, both born via a surrogate.
In the divorce proceedings, Donatacci has filed for primary physical custody of their children together, and spousal support as well.
Grammer, 55, has been married twice before. He and Doreen Alderman wed in 1982 and together had daughter Spencer the following year. In 1992, he married former exotic dancer Leigh-Anne Cushany. Around that time, Grammer had a daughter, Greer, with hairdresser Barrie Bucker.
Grammer was recently nominated for a Tony Award for his performance in La Cage Aux Folles on Broadway. Meanwhile, Donatacci is rumored to have joined the cast of Bravo's upcoming "Real Housewives of Beverly Hills."