Newmarket Heath is a 279.3-hectare-large (690-acre) biological Site of Special Scientific Interest in Newmarket in Suffolk. It covers most of Newmarket Racecourse.

Most of this site is chalk grassland, and it has areas of chalk heath, a rare habitat in Britain. There is a rich variety of flowering plants, including a nationally rare species listed in the British Red Data Book of threatened species and five nationally uncommon ones. The dominant grasses are upright brome and sheep's fescue.

52°14′N 0°22′E / 52.24°N 0.37°E / 52.24; 0.37