Leif Daniel Tjernström (born 19 February 1974) is a Swedish former professional footballer who played as a midfielder.

Tjernström started his footballing career at Bråtens IK before spending three seasons in Division 2 Västra with KB Karlskoga.

[1] He scored the game-winning goal against IFK Göteborg in November 2009 when AIK secured their first Allsvenskan title in nine years.

[1] He made his last appearance for AIK during the 2013 Allsvenskan season in a 2–1 win against Elfsborg, which was his 395th competitive game for the club.

[2][3] He made his fifth and final appearance for Sweden on 27 November 1999 in a friendly game against South Africa, playing for 59 minutes before being replaced by Tobias Linderoth in a 1–0 loss.