Mattias Beck is a Swedish left winger on AIK.
Beck has played nearly all of the last ten seasons in the AIK system, starting in 1999 when he played in 14 games for the J18 squad. In 2001, he made his senior debut, appearing in 2 games for AIK in the Elitserien. In 2002, he played another full season at the senior level, scoring 15 goals and 32 points. He played two seasons with Oskarshamn during the NHL lockout and the following season, as well as joining HV71 for 8 games in 2006. He returned to AIK in 2006, and set a career high 39 points in 2007-08.