George Alexandrovich Ostrogorsky (Russian: Георгий Александрович Острогорский, romanized: Georgiy Aleksandrovich Ostrogorskiy; Serbian: Георгије Александрович Острогорски, Georgije Aleksandrovič Ostrogorski; 19 January 1902 – 24 October 1976) was a Russian-born Yugoslav historian and Byzantinist who was widely known for his achievements in Byzantine studies. He was a professor at the University of Belgrade.