Gregory Jay Leon (born May 1958) is a Los Angeles hard rock guitarist notable for his stints in Quiet Riot and Dokken. He was also in a band called Suite 19 with Gary Holland, who was later replaced by Tommy Lee.Leon is considered an influential and important musical personality in the Hollywood Hard Rock/Heavy Metal scene of the late 70s and early 80s, playing an integral part in the successive fortunes of the acts he was associated with.