Marcin Tarczyński (born 10 September 1990 in Nowy Dwór) is a Polish swimmer, who specialized in freestyle and backstroke events.

[1][2] He is a silver medalist at the 2008 European Junior Swimming Championships in Belgrade, Serbia, and later represented Poland at the 2012 Summer Olympics in London.

While studying in the United States, Tarczynski also holds a school record and 200 m individual medley title at the 2012 NCAA Men's Swimming and Diving Championships.

Tarczynski reached his first international spotlight at the 2008 European Junior Swimming Championships in Belgrade, Serbia, where he earned a silver medal in the 100 m freestyle (50.11).

[6][7] He challenged seven other swimmers in heat five, including France's top favorite Camille Lacourt and Russia's Arkady Vyatchanin, bronze medalist in Beijing four years earlier.