The Diocese of Gradisca (Latin: Dioecesis Gradisca) was a Roman Catholic diocese located in the town of Gradisca d'Isonzo in the Province of Gorizia in Friuli-Venezia Giulia for the short-lived union (only three years) of the Dioceses of Trieste, Gorizia and Pedena. In 1791, it was united with the re-established Archdiocese of Gorizia to form the Archdiocese of Gorizia e Gradisca.[1][2] In 1986, it was restored as the Titular Archiepiscopal See of Gradisca.[2]