The 2005 Texas Longhorn football team represented the University of Texas at Austin during the 2005 NCAA Division I-A football season, winning the Big 12 Conference championship and the national championship. The team was coached by Mack Brown, led on offense by quarterback Vince Young, and played its home games at Darrell K. Royal – Texas Memorial Stadium.
The team's penultimate victory of the season, the Big 12 Championship Game, featured the biggest margin of victory in the history of that contest. They finished the season by winning the 2006 Rose Bowl against the USC Trojans for the national championship. Numerous publications have cited this victory as standing among the greatest performances in college football history, and ESPN awarded the 2006 ESPY Award for the "Best Game" in any sport to the Longhorns and the Trojans. The Longhorns finished as the only unbeaten team in NCAA Division I-A football that year, with thirteen wins and zero losses.
Texas earned its second Big 12 Conference football championship to make 27 conference championships total, including 25 in the Southwest Conference. It was their fourth national championship in football and the ninth perfect season in the history of Longhorn football.
The team set numerous school and NCAA records, including their 652 points which set an NCAA record for points scored in a season. After the season ended, six Longhorns from this championship team joined professional football teams through the 2006 NFL Draft. Seven more Longhorns followed suit in the 2007 NFL Draft and they were joined by two free agents. Another nine followed through the 2008 Draft and free-agency to make a total of twenty-four players who entered into the National Football League (NFL).