Kornilenko began his career in his native Belarus as a trainee with FC Dinamo Minsk before joining his hometown club. After an unsuccessful half a season with Vitebsk he returned to Minsk, where he spent three seasons before moving to Ukraine with Dynamo Kyiv and Dnipro Dnipropetrovsk.
In 2008 he moved to the Russian Premier League with FC Tom Tomsk, with whom he enjoyed a successful first season. On 19 July 2009 FC Zenit signed the striker until December 2013. The Russian club had needed a new striker after a serious injury to Danny and after transfer listing Fatih Tekke. On 9 March 2010 Kornilenko was loaned back to Tom Tomsk for the remainder of the 2009–10 season. He returned to Zenit in the summer of 2010 but was loaned out again, this time to Rubin Kazan, until January 2011. On 31 January 2011, Kornilenko signed on loan for English Premier League club Blackpool, turning down a move to Standard Liege in the process.