Kari Martonen (born 13 March 1963 in Valkeakoski) is a Finnish football manager and former player. He also works as an assistant manager of the Finland U21 squad.
As a player, he played in total of 248 matches and scored 22 goals for HJK and FC Haka. After retiring as a player, he started working as a youth coach at his former club Haka and soon became the assistant manager under Olli Huttunen. In 2006, he became the assistant manager under Mika Lehkosuo at FC Honka.
In November 2009 as Ville Priha was sacked from JJK, Martonen took over as a head coach, signing a three-year contract with JJK.Mestaruussarja: 1985, 1987, 1988
Finnish Cup: 1982
Finnish Cup: 2002
Coach of the Month: April 2010