William Drew Washburn (January 14, 1831 – July 29, 1912) was an American politician. He served in both the United States House of Representatives and the United States Senate as a Republican from Minnesota. Three of his seven brothers became politicians: Elihu B. Washburne, Cadwallader C. Washburn, and Israel Washburn, Jr.  He was also cousin of Dorilus Morrison, the first mayor of Minneapolis. He served in the 46th, 47th, 48th, 51st, 52nd, and 53rd congresses.