Sergei Kukushin was drafted out of HC Minsk of the Belarus League. Missed the 2002-03 season to injury. He previously saw action in the Belarussian League during 2001-02 and 2003-04 seasons. Started 2004-05 season in the USHL and played 19 games for the USHL Indianapolis Ice in 2004-05, scoring just three points. He was -5 and had 50 penalty minutes. He moved in December 2004 to the New England Junior Huskies of the EJHL. Kukushin has represented Belarus at both the 2004 and 2005 U-20 WJC tournaments. Prior to that, he played with the U-18 national squad in 2003.
2005-06: Kukushin represented Belarus at the World Junior Championships in 2005, notching a goal and 14 PIMs in six games. He spent the year in Russia’s Vysshaya Liga with Kapitan Stupino, where he recorded 21 goals and 32 points in 45 games.
2006-07: The Minsk-native made his Russian Super League debut. He spent five games with Dynamo Moscow (1+1=2) and 25 with Lada Togliatti (4+1=5). He would represent Belarus in the World Championships, but he went scoreless in seven contests.
2007-08: Kukushin would return to Belarus to play with Metallurg Zhlobin. He scored 14 goals and 25 points in 34 games. For the fifth straight year, he would represent his nation on the international stage. He once again joined Belarus at the World Championships; he appeared in six games registering his first point at the WC’s.