Harold P. Boas (born June 26, 1954, in Evanston, Illinois, United States) is an American mathematician.
He received his A.B. and S.M. degrees in applied mathematics from Harvard University in 1976 and his Ph.D. in mathematics from the Massachusetts Institute of Technology in 1980 under the direction of Norberto Kerzman. He was a J. F. Ritt Assistant Professor at Columbia University (1980–1984) before moving to Texas A&M University, where he advanced to the rank of associate professor in 1987 and full professor in 1992. He has held visiting positions at the University of North Carolina at Chapel Hill and the Mathematical Sciences Research Institute at Berkeley.
He has published over thirty papers, including Reflections on the arbelos, American Mathematical Monthly 113 (2006), 236–249, and has also translated several dozen papers and a book from Russian into English. He is a winner of the Lester R. Ford Award (2007) of the MAA and a co-winner of the Stefan Bergman Prize (with Emil J. Straube, 1995) of the AMS. In 2012 he became a fellow of the American Mathematical Society.
He is the son of two noted mathematicians Ralph P. Boas, Jr, and Mary L. Boas. He revised and updated his father's book A Primer of Real Functions for the fourth edition.