Ambrosio Bernardo O'Higgins y O'Higgins, 1st Marquess of Osorno (1720 – 19 March 1801) born Ambrose Bernard O'Higgins (Ambrós Bearnárd Ó hUiginn, in Irish), was an Irish-Spanish colonial administrator and a member of the O'Higgins family.
He served the Spanish Empire as a captain general (i.e., military governor) of Chile (1788–1796) and as the Viceroy of Peru (1796–1801). He was the father of Chilean independence leader Bernardo O'Higgins.