Samuel Anthony Alito Jr. OMRI (born April 1, 1950) is an American jurist who serves as an associate justice of the Supreme Court of the United States. He was nominated to the high court by President George W. Bush on October 31, 2005, and has served on it since January 31, 2006. After Antonin Scalia, Alito is the second Italian American justice to serve on the U.S. Supreme Court.

Alito was raised in Hamilton Township, New Jersey, and was educated at Princeton University and Yale Law School. After graduating from law school, he worked as an assistant attorney general for the Office of Legal Counsel and served as the U.S. Attorney for the District of New Jersey. In 1990, Alito was appointed as a judge on the U.S. Court of Appeals for the Third Circuit, where he served until joining the Supreme Court. He has called himself a "practical originalist" and has been described as one of the Court's "most conservative justices".

Alito has written majority opinions in the landmark cases McDonald v. Chicago (2010), Burwell v. Hobby Lobby (2014), Janus v. AFSCME (2018), and Dobbs v. Jackson Women's Health Organization (2022).