Nicolai Yuryevich Reshetikhin (Russian: Николай Юрьевич Решетихин, born October 10, 1958 in Leningrad, Soviet Union) is a mathematical physicist, currently a professor of mathematics at the University of California, Berkeley and a professor of mathematical physics at the University of Amsterdam (Korteweg-de Vries Institute for Mathematics). His research is in the fields of low-dimensional topology, representation theory, and quantum groups. His major contributions are in the theory of quantum integrable systems, in representation theory of quantum groupsand in quantum topology. He and Vladimir Turaev constructed invariants of 3-manifoldswhich are expected to describe quantum Chern-Simons field theory introduced by Edward Witten.