Jacob "Jaap" Korevaar (born 25 January 1923, Lange Ruige Weide) is a Dutch mathematician. He was part of faculty of University of California, San Diego and University of Wisconsin–Madison, as well as the University of Amsterdam.Korevaar won the 1987 Lester R. Ford Award, and the 1989 Chauvenet Prize, for an essay on Louis de Branges de Bourcia's proof of the Bieberbach conjecture.