Reginald Lawson Waterfield (12 April 1900 – 10 June 1986 in Woolston) was a British hematologist known for his work in amateur astronomy. In particular astrometry and the photographing of comets. He served as Director of the British Astronomical Association Mars Section from 1931-1942 and its President from 1954-1956. After World War II he had to use a wheelchair due to polio. He won the 1942 Jackson-Gwilt Medal and 1645 Waterfield is, in part, named for him. The name also honours his cousin William Francis Herschel Waterfield.
He was the son of Reginald Waterfield, a prominent teacher and clergyman.