Sergei Ivanovich Grigoryants (Russian: ?????´? ???´????? ????????´??, Ukrainian: ?????´? ???´????? ????????´??, born 12 May 1941, Kiev, Ukrainian SSR, Soviet Union) is a Soviet dissident and former political prisoner, journalist, literary critic, chairman of the Glasnost Defense Foundation.
He was imprisoned for 10 years in Chistopol jail as a political prisoner for anti-Soviet activities, from 1975 to 1980 and then four more years starting in 1983 on similar charges.