David Robert Morrison (born July 29, 1955, in Oakland, California) is an American mathematician and theoretical physicist. He works on string theory and algebraic geometry, especially its relations to theoretical physics. Although Morrison began his career as a mathematician in classical algebraic geometry, in his later career he has also been a string theorist. He works on the interfaces and mutual fertilization of algebraic geometry and string theory, especially mirror symmetry. He is a co-editor of selected works of his thesis supervisor Phillip GriffithsPhillip Griffiths.