Super Bowl XXXVIII was an American football game between the National Football Conference (NFC) champion Carolina Panthers and the American Football Conference (AFC) champion New England Patriots to decide the National Football League (NFL) champion for the 2003 season. The Patriots defeated the Panthers by a score of 32–29. The game was played at Reliant Stadium in Houston, Texas, on February 1, 2004. At the time, this was the most watched Super Bowl ever with 89.8 million viewers.

The Panthers were making their first ever Super Bowl appearance after posting an 11–5 regular season record. They also made it the second straight year that a team from the NFC South division made the Super Bowl, with the Tampa Bay Buccaneers winning Super Bowl XXXVII. The Patriots, led by head coach Bill Belichick and quarterback Tom Brady, were seeking their second Super Bowl title in three years after posting a 14–2 record.

NFL fans and sports writers widely consider this game one of the most well-played and thrilling Super Bowls; following the game Sports Illustrated writer Peter King hailed it as the "Greatest Super Bowl of all time." Although neither team could score in the first and third quarters, making it the first Super Bowl with two scoreless quarters, they ended up with a combined total of 868 yards and 61 points. The game was scoreless for a Super Bowl record 26:55 before the two teams combined for 24 points prior to halftime. The clubs then combined for a Super Bowl record 37 points in the fourth quarter. The contest was finally decided when the Patriots kicker Adam Vinatieri's 41-yard field goal was made with four seconds left. Patriots quarterback Tom Brady was named Super Bowl MVP for the second time in his career.

The game is also known for its controversial halftime show in which Janet Jackson's breast, adorned with a nipple shield, was exposed by Justin Timberlake for about half a second, in what was later referred to as a "wardrobe malfunction". Along with the rest of the halftime show, it led to an immediate crackdown by the Federal Communications Commission (FCC), and widespread debate on perceived indecency in broadcasting.

NFL owners voted to award Super Bowl XXXVIII to Houston during their November 1, 2000, meeting held in Atlanta. It marked the second Super Bowl held in the Houston area, the first was VIII played at Rice Stadium. Three Super Bowls host sites were selected during the meeting, XXXVIII, XXXIX, and XL. However, XXXIX was the only one of the three that involved a competitive voting process. The vote for XXXVIII was mostly a formality, as Houston had been tentatively preselected for the game, contingent on satisfying a series of basic requirements. No other cities were considered for XXXVIII. Back in 1998, NFL commissioner Paul Tagliabue had singled out San Diego (Qualcomm Stadium) as the likely host for XXXVIII. However, San Diego ultimately got XXXVII instead after the league took away that game from San Francisco. After their lone previous effort of hosting the Super Bowl (1974), the city of Houston had bid numerous times, unsuccessfully, to host the game a second time. Both Rice Stadium and later the Astrodome had been proposed, but both were rejected by owners for various reasons. Despite being indoors, the Astrodome lacked capacity, which would require temporary seating. The closest the Astrodome came to winning a bid was for XXIX when it finished a close second in the voting. Houston then lost the Oilers after 1996, and were without an NFL franchise for five seasons.

On October 6, 1999, the NFL owners voted to award the city of Houston the 32nd expansion franchise. The Houston Texans would begin play in 2002, and would play their home games in a brand new facility, Reliant Stadium. In the weeks leading up to the expansion vote, the negotiations included a promise by the NFL that Houston, if they were to win the expansion vote, would receive a Super Bowl 'as soon as possible' at the new stadium. Since future host sites had already been selected through XXXVII (January 2003), the soonest Houston could host would be XXXVIII (February 2004). That satisfied the NFL's rule that required new stadiums to wait until at least their second year of operation before hosting a Super Bowl, in order to iron out any logistical issues or construction delays. About a year after being awarded the expansion franchise, on November 1, 2000, the Houston task force, led by mayor Lee Brown, Texans owner Bob McNair, representatives from the Houston Livestock Show and Rodeo, and other local leaders, delivered their formal presentation. Houston was awarded XXXVIII without opposition. Jacksonville won the vote for XXXIX, and Detroit was awarded XL.

This was the first Super Bowl to be played in a retractable roof stadium. However, it would remain closed during the game. This game marked a six-month stretch for the state of Texas hosting the Super Bowl, the NCAA Final Four (Alamodome) and the MLB All-Star Game (Minute Maid Park). Super Bowl XXXVIII was the first Super Bowl to be scheduled for the first Sunday of February; subsequent Super Bowls through LV would follow this format. XXXVI had previously been held on the first Sunday of February, but that came as a result of the NFL pushing back the 2001 playoffs by a week as a result of the September 11 attacks.

The Panthers made their first trip to the Super Bowl after posting a one-win regular season just two years earlier. The franchise was in its ninth year of existence, joining the league as an expansion team in 1995.