Edwin Hewitt (January 20, 1920, Everett, Washington – June 21, 1999) was an American mathematician known for his work in abstract harmonic analysis and for his discovery, in collaboration with Leonard Jimmie Savage, of the Hewitt–Savage zero–one law. He received his Ph.D. in 1942 from Harvard University, and served on the faculty of mathematics at the University of Washington from 1954. Hewitt pioneered the construction of the hyperreals by means of an ultrapower construction (Hewitt, 1948).