James T. McDermott (September 22, 1926 – June 21, 1992) was a Pennsylvania judge and politician who served on the state's Supreme Court from 1981 until his death in 1992. Before joining the court, he was active in Philadelphia politics as a Republican candidate for Congress in 1958, city council in 1962, and mayor in 1963. He was a trial court judge on the Court of Common Pleas from 1965 to 1981.