Newmarket is a town in Rockingham County, New Hampshire, United States. The population was 8,027 at the 2000 census. Some residents are students and employees at the nearby University of New Hampshire in Durham. The primary settlement in town, where over 63% of the population resides, is defined as the Newmarket census-designated place, or CDP, and is located at the junction of New Hampshire Routes 108 and 152, adjacent to the Lamprey River.