Stafford beat out six other players who received votes from a nationwide panel of 50 media members who regularly cover the league. Stafford fought through injuries his first two seasons, then threw for more than 5,000 yards in 2011 to lead Detroit to its first playoff berth in 12 years.
Stafford is the first Lion and the ninth quarterback to win the award since its inception in 1998.
Stafford stressed the team's success was more important than anything he did individually. Detroit made the playoffs for the first time since 1999.
"That's what people are judged on this time of year," said Stafford, who added the Lions are capable of much more than just earning a wild-card berth and losing in the opening round. ""We have great talent around me. We've got it all. We're still proving ourselves."
Stafford not only had a great comeback year from shoulder and knee injuries in his first two pro seasons, but he was exceptional at leading comebacks in games. He helped Detroit become the first team in NFL history to rally and win four games after being down by at least 13 points, including 20-plus point comebacks at Dallas and Minnesota.
"He doesn't waver," receiver Nate Burleson said. "When you have a quarterback that isn't worried, who always has a smile on his face and lets the ball release out of his hand like a cannon, you're not worried at all. You look at him like he's the captain of the boat and if he's ready to sail, we're going to go to sea with him."
Stafford completed 63.5 percent of his passes for 5,038 yards - only the fourth quarterback to go over 5,000 yards - and 41 touchdowns.
AP Sports Writer Larry Lage in Detroit contributed to this story.