Sergei Ivanovich Dovzhenko (born June 30, 1972, Mariupol, Donetsk Oblast, Ukrainian SSR) is a Ukrainian-Soviet serial killer, a former operative of the Mariupol police.
He confessed to committing 19 murders between November 1998 and May 2002 in his native city.
Among his victims are a 12-year-old girl, four employees of the Ministry of Internal Affairs of Ukraine and one Yugoslav citizen.