Peppers was selected over fellow finalists Florida's Alex Brown, Oklahoma's Rocky Calmus, Syracuse's Freeney in a final round of voting.
"I don't think anyone expected me to win," Peppers said. "It feels great. It's a great honor. I'm still kind of in shock. I knew I had a chance to win it, but I didn't think I would."
Peppers, who piled up 15 sacks as a sophomore, ran his career total to 30 1/2. Peppers intercepted three passes this season, the most by a lineman in school history and returned one for a touchdown.
The Lombardi winner is presented to the college lineman who, in addition to outstanding performance on the field, best exemplifies the characteristics and discipline of Vince Lombardi.