Stephen H. Schanuel (14 July 1933 – 21 July 2014) was an American mathematician working in the fields of abstract algebra and category theory, number theory, and measure theory.^[1][2]

While he was a graduate student at University of Chicago, he discovered Schanuel's lemma, an essential lemma in homological algebra.^[2] Schanuel received his Ph.D. in mathematics from Columbia University in 1963, under the supervision of Serge Lang.^[2]

Shortly thereafter he stated a conjecture in the field of transcendental number theory, which remains an important open problem to this day.^[2] Schanuel was a professor emeritus of mathematics at University at Buffalo.^[1]

• Lawvere, F. William; Schanuel, Stephen Hoel (2009) [1997]. Conceptual Mathematics: A First Introduction to Categories (2nd ed.). Cambridge University Press. ISBN 978-0-521-89485-2.