2001 Buffalo Bills season

The 2001 season was the Buffalo Bills' 42nd season. Previous head coach Wade Phillips was fired, and was replaced by Tennessee Titans defensive coordinator Gregg Williams. At 3–13, they finished the season with the worst record in the whole American Football Conference and at last place in the AFC East division for the first time since 1985.

John Butler, who had been the Bills' general manager from 1993 to 2000, left to take the same position with the San Diego Chargers. He was replaced by Tom Donahoe, who would remain with the Bills through the 2005 season.

In the wake of Buffalo's quarterback controversy, Doug Flutie was released by the Bills, prior to the season and followed Butler to San Diego. Buffalo named Rob Johnson their starting quarterback for the 2001 season, which would ultimately be his last in Buffalo. Bills defensive end Marcellus Wiley, linebacker Sam Rogers, and linebacker John Holecek also left Buffalo for San Diego in 2001, leaving a gap in Buffalo's defense. The special teams also saw a major overhaul. Placekicker Steve Christie was also among the defectors to San Diego, forcing the Bills to sign rookie Jake Arians (son of longtime offensive coordinator Bruce Arians) as a replacement, then after several weeks of Arians's poor play, Shayne Graham. Chris Mohr left for the Atlanta Falcons and was replaced by Brian Moorman, who would stay with the team for the next eleven seasons. This year the Bills switched to a 4-3 defensive scheme after using their 3-4 scheme since 1979.