Santa Rosa is a city in and the county seat of Guadalupe County, New Mexico, United States. As of the 2020 census, Santa Rosa had a population of 2,850. It lies between Albuquerque and Tucumcari, situated on the Pecos River at the intersection of Interstate 40 (I-40), U.S. Route 54 (US 54), and U.S. Route 84 (US 84). The city is located on the western edge of the Llano Estacado or "staked plains" of eastern New Mexico and western Texas.