Daniel Hadley Sumner (September 15, 1837 – May 29, 1903) was a U.S. Representative from Wisconsin.

He attended the common schools, and Prairie Seminary, in Richland.

He was then admitted to the bar in 1868, and commenced practice in Kalamazoo, Michigan.

He moved to Oconomowoc, Wisconsin in 1868 and practiced law.

He moved to Waukesha, Wisconsin in 1870, and continued the practicing law.