The Pittsburgh Steelers defeated the Seattle Seahawks 21-10 in Super Bowl XL. The Steelers joined the Dallas Cowboys and San Francisco 49ers as the only NFL franchises to win five Super Bowl championships. They also became the fourth wild card team to win the Super Bowl, and the first one to do so without playing at least one playoff game at home. The game was televised on ABC and earned a 41.6 rating nationally, making it the highest-rated Super Bowl telecast, and highest-rated sports telecast, of all-time. The game was the second one held in the Detroit area, but the first actually in the city limits at brand new Ford Field. Steelers wide receiver Hines Ward caught 5 passes for 123 yards. He also caught his only touchdown of the game on a flanker option throw by fellow wideout Antwaan Randle El, and Hines was named the Most Valuable Player of the game. Broadcaster John Madden also established history as the first to broadcast the Super Bowl as a member of three different television networks.

The Steelers finished the regular season with an 11-5 record, and finished runners-up to Cincinnati in the AFC Central due to a divisional record tiebreaker. As the #6 seed in the AFC playoffs, this meant the Steelers would have to win three road playoff games just to reach the Super Bowl. But the Steelers, led by running back Jerome Bettis, were undaunted. After knocking off the Bengals in the wild card round, they shocked the top-seeded Indianapolis Colts in the division round before knocking off the Denver Broncos to win the AFC Championship Game.

The New Orleans Saints were forced to play all of their 2005 games away from home because of the aftermath from Hurricane Katrina. The storm not only gutted the city of New Orleans, but also forced the Superdome to initially act as a safe haven for stranded residents. So after playing a "home game" at Giants Stadium against the New York Giants, they split the remainder of their home schedule between Tiger Stadium at LSU and the Alamodome in San Antonio.