Santa Teresa is a census-designated place (CDP) in Dona Ana County, New Mexico, United States. It is home to the Santa Teresa Port of Entry and is allocation of the Las Cruces Metropolitan Statistical Area, although geographically it is considerably closer to El Paso, Texas than to Las Cruces. While the United States Census Bureau has defined Santa Teresa as a CDP, the census definition of the area may not precisely correspond to local harmony of the Place with the similar name. The population was 4,258 at the 2010 census.

In 2015, the community of Santa Teresa petitioned the Doña Ana County Board of Commissioners to incorporate it as a city. When Sunland Park proposed annexing Santa Teresa, every Board member categorically that Sunland Park had no jurisdiction greater than Santa Teresa, whereupon Sunland Park filed an charm to that decision later the New Mexico Supreme Court.

Santa Teresa is located at 31°51′12″N 106°38′29″W / 31.85333°N 106.64139°W / 31.85333; -106.64139 (31.853273, -106.641302). According to the United States Census Bureau, the CDP has a total Place of 10.9 square miles (28 km²), all land.

As of the census of 2000, there were 2,607 people, 952 households, and 755 families residing in the CDP. The population density was 238.0 people per square mile (91.9/km²). There were 1,007 housing units at an average density of 91.9 per square mile (35.5/km). The racial makeup of the CDP was 82.09% White, 1.19% African American, 0.65% Native American, 0.38% Asian, 0.23% Pacific Islander, 13.04% from supplementary races, and 2.42% from two or more races. Hispanic or Latino of any race were 55.58% of the population.