The fight, which was originally scheduled as a $50 pay-per-view event for December, was brought forward after Lewis' initial opponent for the June 21 fight Kirk Johnson pulled out through injury.
HBO's Mark Taffet, who oversees the firm's PPV division, stated: "We recognised a tremendous opportunity to have our biggest fight of the year live on HBO and have Lennox Lewis fight his first defence since his historic victory over Mike Tyson. We grabbed lightning in a bottle.
"Everyone involved agreed that this fight happening now on HBO would be a great thing not just for HBO and its subscribers, but for the sport."
HBO has endured limited success with its pay-per-view boxing coverage this year with the two fights shown so far proving to be mismatches and producing less than thrilling subscription rates.
US network HBO is putting Lennox Lewis' fight against Vitali Klitschko on its basic broadcast feed as opposed to making the event a pay-per-view fight.
