Isaiah ben Elijah di Trani (the Younger) (Hebrew: ישעיה בן אליהו דטראני) was an Italian Talmudist and commentator who lived in the 13th century. He was the grandson, on his mother's side, of Isaiah (ben Mali) di Trani the Elder. He is usually quoted as ריא"ז (= "R. Isaiah Acharon, ז"ל"), or (ריב"א = "R. Isaiah ben Elijah").