Major General Sir Donald Johnstone McGavin CMG DSO CStJ (19 August 1876 – 8 May 1960) was a New Zealand surgeon, army health administrator and medical administrator. He was born in Chatham, Kent, England. He qualified as a Doctor of Medicine in 1901. In the 1919 New Year Honours, McGavin was made an additional Companion of the Order of St Michael and St George. He was appointed a Knight Bachelor in the 1921 King's Birthday Honours. In 1935, he was awarded the King George V Silver Jubilee Medal. In 1946 he was appointed as a Commander of the Order of St John.