Mariusz Witecki (born 10 May 1981) is a Polish former professional road bicycle racer, who rode professionally between 2003 and 2016 for the Team Volksbank, Mróz–Active Jet, CCC–Polsat–Polkowice, Bank BGŻ and Domin Sport teams. He now works as the team manager for UCI Continental team Voster Team.

Born in Kielce, Witecki won the five-day Course de la Solidarité Olympique stage race in Poland in July 2012, beating Team NetApp's Bartosz Huzarski by five seconds.