Ornstein may refer to:Axel Ornstein, Swedish chess master Donald Samuel Ornstein, American mathematician Jonathan G. Ornstein, CEO of Mesa Air Group, Inc. Leo Ornstein (1895–2002), Russian-American composer Leonard Salomon Ornstein (1880–1941), Dutch physicist known for the Ornstein–Zernike equation and the Ornstein–Uhlenbeck process Michael Marisi Ornstein, American actor Norman J. Ornstein, American political scientist Robert Ornstein, American psychologist Severo Ornstein, American computer scientist and son of Leo Ornstein
