Super Bowl XX was an American football game between the National Football Conference (NFC) champion Chicago Bears and the American Football Conference (AFC) champion New England Patriots to decide the National Football League (NFL) champion for the 1985 season. The Bears defeated the Patriots by the score of 46–10, capturing their first NFL championship (and Chicago's first overall sports victory) since 1963, three years prior to the birth of the Super Bowl. Super Bowl XX was played on January 26, 1986 at the Louisiana Superdome in New Orleans. This was the first of nine Super Bowl appearances for New England.

To date, it is the fourth, and most recent, Super Bowl where both teams were making their Super Bowl debuts. Presently, this would only occur again if the Detroit Lions faced either the Cleveland Browns, Jacksonville Jaguars, or the Houston Texans. Additionally, this is currently the only Super Bowl to match teams where both head coaches, Mike Ditka for the Bears and Raymond Berry for the Patriots, were inducted into the Pro Football Hall of Fame as players, though Ditka did not get selected for the Hall of Fame until 1988, after Super Bowl XX was played. The Bears entered the game after becoming the second team in NFL history to win 15 regular season games. With their then-revolutionary 46 defense, Chicago led the league in several defensive categories, outscored their opponents with a staggering margin of 456–198, and recorded two postseason shutouts. The Patriots were considered a Cinderella team during the 1985 season, and posted an 11–5 regular season record, but entered the playoffs as a wild card because of tiebreakers. But defying the odds, New England posted three road playoff wins to advance to Super Bowl XX.

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