Frank Baker (August 22, 1841 – September 30, 1918) was an American physician and superintendent of the National Zoo in Washington, DC.

[1] In 1863, he left the army and became a clerk in Washington DC.

There he became friends with Walt Whitman and John Burroughs.

In 1881, he was involved with the treatment of President James Garfield after he had been shot, and there he met George Kennan and Alexander Graham Bell.

In 1883, Baker became a professor of anatomy at Georgetown University, and in 1888 he co-founded the National Geographic Society.