Leonard George Goodwin CMG FRS (11 July 1915 – 25 November 2008) was a British protozoologist noted for his work on testing the effectiveness of chemical compounds in treating tropical diseases. He was born in London to a shoe shop manager, and became interested in nature thanks to holidays spent with his grandfather, a gamekeeper, and his uncle, a pharmacist. He was educated at William Ellis School before being accepted into University College London to study botany and zoology. After graduating he went to the College of the Pharmaceutical Society and studied pharmacy, graduating in 1935. He became a demonstrator at the college under J H Burn and at his urging took further degrees in medicine and physiology.