Vea revealed the news in a social media post in which he also thanked his coaches, teammates and fans.
A 6-foot-5, 340-pound space-eating interior lineman, Vea is projected by ESPN's Todd McShay to be a first-round draft pick. He was the centerpiece of a Washington defense that allowed the fewest rushing yards in the FBS during the regular season.
Vea's decision to turn pro didn't come as a surprise. It was first reported by the Seattle Times after Washington's 35-28 loss to Penn State at the Playstation Fiesta Bowl on Saturday night; he confirmed the choice Monday.
"As I begin the next chapter of my football career, I will never forget where it all began," he wrote in the post Monday. "The University of Washington is a special place. ... I cherish every game I was able to play in purple and gold."
Vea won the Pac-12 defensive player of the year award this season after making 43 tackles and 3.5 sacks.