Officer Jarius Daugherty said in an email that the rapper, whose given name is Shad Moss, was arrested early Saturday.
Police were called to an address in Midtown Atlanta around 4:15 a.m. When they arrived, a woman named Leslie Holden told them she'd been assaulted by Moss. Officers also spoke with Moss, who said Holden assaulted him.
Police say both Moss and Holden had "visible minor injuries." Officers couldn't tell who was the primary aggressor, so both were charged with battery.
Police say both were being processed and would be taken to the Fulton County jail. It wasn't clear if either had an attorney who could comment.
Police say the investigation is ongoing.