Charles "Chuck" Billy (born June 23, 1962) is an American vocalist, who is best known as the lead vocalist for the thrash metal band Testament. 　　His influences include Rob Halford, Ronnie James Dio, Bruce Dickinson, Phil Mogg, James Hetfield, Ozzy Osbourne, Geddy Lee, Bon Scott, Steven Tyler, Alice Cooper, Robert Plant and Klaus Meine.