Andrew James Granville (born 1962) is a British mathematician, working in the field of number theory.
He has been a faculty member at the Université de Montréal since 2002. Before moving to Montreal he was a mathematics professor at University of Georgia (UGA) from 1991 until 2002. He was a section speaker in the 1994 International Congress of Mathematicians together with Carl Pomerance from UGA.
Granville received his Bachelor of Arts (Honours) (1983) and his Certificate of Advanced Studies (Distinction) (1984) from Trinity College, Cambridge University. He received his Ph.D. from Queen's University in 1987 and was inducted into the Royal Society of Canada in 2006.
Granville's work is mainly in number theory, in particular analytic number theory. Along with Carl Pomerance and W. R. (Red) Alford he proved the infinitude of Carmichael numbers in 1994. This proof was based on a conjecture given by Paul Erdős.
Granville won a Lester R. Ford Award in 2007 and again in 2009. In 2008, he won the Chauvenet Prize from the Mathematical Association of America for his paper "It is easy to determine whether a given integer is prime". In 2012 he became a fellow of the American Mathematical Society.