Eustachy is a given name. Notable people with the name include:
Eustachy Erazm Sanguszko (1768–1844), Polish general and politician Eustachy Sapieha (1881–1963), Polish nobleman, prince, politician, Minister of Foreign Affairs and deputy to the Polish parliament Eustachy Stanisław Sanguszko (1842–1903), Polish noble (szlachcic), conservative politician Eustachy Tyszkiewicz (1814–1874), Polish–Lithuanian noble, archaeologist and historian from the former Grand Duchy of Lithuania Larry Eustachy (born 1955), former NCAA Men's Basketball coach