Cotija is a municipality in the Mexican state of Michoacán. The municipality has an area of 504.05 km², and is bordered to the north by Jiquilpan and Villamar, to the east by Tocumbo, and to south by the state of Jalisco. The municipality had a population of 18,207 inhabitants according to the 2005 census. Its municipal seat is the city of Cotija de la Paz.