Grinstein is a surname. Notable people with the surname include:
Elyse Grinstein (1929–2016), American architect and art collector Gerald Grinstein (born 1932), American businessman Gidi Grinstein, Israeli societal entrepreneur Hyman Grinstein, American educator and history Stanley Grinstein (1927–2014), American businessman, master printer, arts collector and patron, philanthropist, and social activist
See also Michal Grinstein-Weiss, American professor