Irwin Ira Shapiro (born October 10, 1929 in New York City) is an American astrophysicist and Timken University Professor at Harvard University.
He has been a professor at Harvard since 1982.
He was the director of the Harvard-Smithsonian Center for Astrophysics from 1982 to 2004.
He is a member of the advisory board of the journal Universe.