David Howells Fleay (January 6, 1907 – August 7, 1993) was an Australian naturalist (someone who studies nature). He was one of the first people to come up with the idea of breeding endangered species in captivity, so they would not go extinct (die out) in the wild. He was also the first person to succeed in breeding platypuses in captivity.

Fleay now has a wildlife park named after him in Queensland.

He died on 7 August 1993 aged 85.