Joon Hyun Kim (born May 26, 1971) is an American attorney who served as the acting United States Attorney for the Southern District of New York from March 2017 to January 2018. He was Deputy U.S. Attorney for the Southern District of New York from July 2015 to March 2017 after serving as the chief of the criminal division since July 2014. From April 2013 to July 2014, Kim was the chief counsel to the U.S. Attorney.