Cemach Feldstein ([t?????h f?ldstajn]; sometimes spelled Tzemach; Hebrew: ??? ?????????; Yiddish: ??????????; Lithuanian: Feldsteinas; Russian: ????? ?????????? ??????????, Semyon Grigorovitch; December 30, 1884 - December 29, 1944 was a Lithuanian educator, author, an education reformist, a culture Zionist activist.
As an educator he was served as the director of several Jewish gymnasiums, the most notable of which was the Hebrew Real-Gymnasium in Kaunas (Kovno), Lithuania (1922-1940), where most of the subjects were taught in Modern Hebrew.
After being deported to the Vilna Ghetto in 1941, Feldstein continued to be a cultural activist.
He became the editor of the ghetto newspaper, translated essays and writings into Hebrew, gave lectures, and was an inspirational coordinator of the ghetto's cultural life.