Jung Jin-young is a South Korean actor. He has starred in numerous films, including Hi! Dharma!, Bunt, and The Case of Itaewon Homicide. Jung is best known for his frequent collaborations with director Lee Joon-ik, as Once Upon a Time in a Battlefield and its sequel Battlefield Heroes, The Happy Life, Sunny, and particularly for his role as King Yeonsan in the hugely successful King and the Clown.

The Case of Itaewon Homicide is a 2009 South Korean crime thriller film, based on the true story of the Itaewon murder case, which shocked Korea when Hongik college student Cho Jung-Pil was found dead at an Itaewon Burger King in 1997. The murder was investigated in 1997 by CID Agents J. Choi, D. Zeliff, T. Barnes and B. Crow. Two troubled U.S. teenagers—Arthur Patterson and Edward Lee—became suspects and were convicted. Patterson was released a year later in a special amnesty and Lee was freed a year after that due to lack of evidence. The case never resulted in further convictions. It stars Jang Keun-suk as Arthur Patterson and Jung Jin-young as his lawyer. Song Joong-ki played the victim. The film had 531,068 admissions in South Korea nationwide.