The 2008 Miami Dolphins season was the franchise's 39th season in the National Football League (NFL), the 43rd overall and the first under new head coach Tony Sparano. During the regular season the Dolphins completed the greatest single-season turnaround in NFL history, going from a 1–15 regular season record in 2007 to an 11–5 record in 2008. The previous record for most improved team one year after a 1–15 season belonged to the 1997 New York Jets, who went 9–7. The 1999 Indianapolis Colts were the only other team to accomplish a 10-game turnaround, winning 13 games after winning 3 in 1998, which was also the first year of the Peyton Manning era. Additionally, Miami won the AFC East, becoming the first team in NFL history to win their division after only having one win the previous season. The division title also snapped the Patriots' 5-year streak of winning the AFC East. Their season would come to an end in the Wild Card round when they were defeated by the Baltimore Ravens, which coincidentally, was also the only team they beat last season in overtime to save the Dolphins from suffering a winless season. With their 11–5 record and division title, the Dolphins had hopes of achieving their first playoff victory since 2000, or to possibly become the first team ever to make the Super Bowl after winning only one game the previous season, similar to how the Carolina Panthers went 1–15 in 2001 and made Super Bowl XXXVIII just two seasons later.

The 2008 Baltimore Ravens season was the franchise's thirteenth season in the National Football League (NFL), the first under head coach John Harbaugh and their seventh season under general manager Ozzie Newsome.