Ko Sung-hyun (Hangul: 고성현; Korean pronunciation: [ko.sʌŋ.ɦjʌŋ]; born 21 May 1987) is a South Korean badminton player affiliated with Gimcheon City Hall. He is a former world number 1 both in the men's and mixed doubles. Ko is a BWF World Champion, two time Badminton Asian Champion, and Asian Games gold medalist.