Frank Merle (born 22 November 1962, in Marseille) is a French mathematician, specializing in partial differential equations and mathematical physics.
After graduation from the École normale supérieure (ENS), Merle received in 1987 his Ph.D. from the University of Paris VI under Henri Berestycki with thesis Contributions a l'etude de certaines equations aux derivees partielles non lineaires de la physique mathematique.
In 1989/90 he was an assistant professor at the Courant Institute of Mathematical Sciences of the University of New York.
From 1998 to 2003 he was a member of the Institut Universitaire de France.
Merle does research on partial differential equations (PDEs) and mathematical physics, notably dispersive nonlinear PDEs such as the nonlinear Schrödinger equation and the Korteweg–De Vries equation, and the study of such PDE solutions which over time break down or diverge (blow up).