Santa Rosa is a city in and the county seat of Guadalupe County, New Mexico, United States. The population was 2,848 at the 2010 census. It lies between Albuquerque and Tucumcari, situated on the Pecos River at the intersection of Interstate 40 and U.S. Route 54 and 84. The city is located on the western edge of the Llano Estacado or "staked plains" of eastern New Mexico and west Texas.