John Ussher

• John Ussher, publisher in 1571 of Aibidil Gaoidheilge agus Caiticiosma, the first book printed in Ireland in the Irish language
• John Ussher (died 1741), Irish MP for Carrick
• John Ussher (died 1749), Irish MP for Dungarvan
• John Ussher (1730–1796), Irish MP for Innistiogue
• John Ussher (priest), Irish Anglican priest
• Johnny Ussher, Canadian gold commissioner