Gil Seong-joon (Korean: 길성준, Hanja: 吉成俊; born December 24, 1977), better known by his stage name Gill (Korean: 길), is a South Korean singer and television personality. He was the main singer of former South Korean hip-hop duo, Leessang.

In 2009, Gil joined Infinite Challenge as a guest and, later on, as a regular co-host. Gil also co-hosted Come To Play. In 2012, Gil joined Voice of Korea as one of the coaches and continued for Season 2. He was caught by police for DUI incident in April 2014 and eventually resigned from any public activity including Infinite Challenge and made the comeback in TV program as a producer for Mnet’s hip-hop survival program, Show Me The Money 5, in 2016.