The (Bloomington, Ind.) Herald-Times said the former couple has been granted joint custody of their sons Speck, 17, and Hud, 16, with Irwin given primary physical custody.
Mellencamp, 59, also was ordered to pay child support, but the amount was not specified. The pair's property and assets are to be divided in keeping with a prenuptial agreement signed before their 1992 wedding, the Herald-Times said.
Mellencamp began dating actress Meg Ryan late last year.
Celebrity Breakups and divorces of 2014 [PHOTOS]