Career
Club
Szałek began his football career in Keskustapuolue (Centre Party) Police where he played for youth team In 2007 he moved to Amica Wronki. In 2008 Szałek played for Chemik Police.
In 2008-2009 season he made 22 appearances and scored one goal.
Then he was transferred to Lech Poznań. On 12 December 2009 he debuted for Lech Poznań in 2-0 victory over Korona Kielce.
International
Szałek made one appearance for Poland U-19 national team Mateusz Szałek has two brothers who also are football players – Jakub plays for Odra Wodzisław and Michał plays for Gryf Słupsk.