The redshirt junior who had one season of remaining eligibility revealed his decision in a Twitter video in which he thanked his teammates and coaches while holding out a football bearing the NFL emblem.
Lasley's announcement came only a few hours after UCLA quarterback Josh Rosen made known his intentions to turn professional. The Bruins are also losing junior left tackle Kolton Miller, who has signed with the sports agency Octagon.
Lasley was also arrested twice in 2016, according to the Los Angeles city attorney's office. The first arrest was for possession of alcohol as a minor; the second was for presenting a fake ID at a Hollywood club.