Mary V. Thomas (April 29, 1944 – August 21, 2014) was an American Pima politician and activist. Thomas was the first woman to serve as the Governor of the Gila River Indian Community, an office she held from 1994 to 2000. She also served as Lieutenant Governor of Gila River Indian Community for two tenures: The first term from 1990 to 1994, prior to becoming governor, and a second term beginning in 2003. An active participant in tribal politics, Thomas was also an activist on issues of importance to Native American communities, including poverty, water rights, and casinos.