Yoo Jung-nam (also Yu Jeong-nam, ; born 12 September 1983) is a South Korean swimmer, who specialized in butterfly events. He represented his nation South Korea at the 2008 Summer Olympics, and has won a career total of four medals (one silver and three bronze) in a major international competition, spanning the 2002 Asian Games and the 2005 East Asian Games. Yoo is also a member of the swimming team and a graduate of physical education at Seoul National University.
Yoo competed for the South Korean swimming team in the men's 200 m butterfly at the 2008 Summer Olympics in Beijing. Leading up to the Games, he topped the field with a time of 2:00.77 to make the FINA B-cut at the Dong-A Swimming Championships in Ulsan. Rallying from sixth at the 150-metre turn in heat two, Yoo put in a late surge on the final lap to edge out the frontrunners Douglas Lennox-Silva of Puerto Rico and Vladan MarkoviÃÂ of Serbia by almost a full-body length for the fourth spot in 2:01.00. Yoo failed to advance into the semifinals, as he placed thirty-fourth out of 44 swimmers in the prelims.