Professor Philip MacDonald Sheppard, F.R.S. (27 July 1921 – 17 October 1976) was a British geneticist and lepidopterist. He made advances in ecological and population genetics in lepidopterans, pulmonate land snails and humans. In medical genetics, he worked with Sir Cyril Clarke on Rh disease. He was born on 27 July 1921 in Marlborough, Wiltshire, England and attended Marlborough College from 1935 to 1939. Sheppard married Patricia Beatrice Lee in 1948. They had three sons. He died of acute leukemia on 17 October 1976.