Darwin Phelps (April 17, 1807 – December 14, 1879) was a Republican member of the U.S. House of Representatives from Pennsylvania.

Darwin Phelps was born in East Granby, Connecticut.

He was left an orphan at an early age and went to live with his grandparents in Portage, Ohio, where he completed preparatory studies.

He studied law in Pittsburgh, was admitted to the bar and commenced practice in Kittanning, Pennsylvania, in 1835.

Phelps served as major of the Twenty-second Regiment, Pennsylvania Volunteer Militia, in 1862.