1. Together with his partner Lee Yong-dae, Jung spent forty weeks as World No 1 in the men's doubles discipline between 2009 and 2012, winning eighteen BWF World Superseries tournaments and placing second at the BWF World Championships on two occasions in 2007 and 2009.
Jung Jae-sung was a two-time winner of the All-England Open, gold medalist at the 2008 Badminton Asian Championships, and won the bronze medal at the 2012 Olympic Games in the final tournament of his professional career.
Jung Jae-sung was born on 25 August 1982 in Jeonju, North Jeolla Province.
Jung Jae-sung started playing badminton at 7, at his local elementary school.
Jung Jae-sung entered the South Korea national badminton team in 2001.
In 2000, Jung Jae-sung was part of the Korean national junior team competed at the World Junior Championships in Guangzhou, China, and Asian Junior Championships in Kyoto, Japan.
In 2003, Jung Jae-sung, who represented Wonkwang University, won the men's doubles title at the National Championships in Gyeonggi partnered with Lee Jae-jin.
In 2004, he and Lee Jae-jin retained their title, and in 2006, Jung Jae-sung repeated his success partnered with Lee Yong-dae.
In 2005, Jung Jae-sung won the Thailand Open with his former partner Lee Jae-jin, beating the Danes Lars Paaske and Jonas Rasmussen in the finals.
In 2006, Jung Jae-sung won the Thailand Open together with Lee Yong-dae; they had a walkover in the final against compatriots Lee Jae-jin, with whom Jung Jae-sung won the last Thailand Open, and Hwang Ji-man.
Jung Jae-sung participated to the 2007 Sudirman Cup with the South Korea team.
In November, Jung Jae-sung won the 2008 China Open Super Series.
Jung Jae-sung's partner went on to get the gold medal in mixed doubles.
On 9 March 2018, at the age of 35, Jung Jae-sung died suddenly of a heart attack at his home in Hwaseong after reportedly suffering from cardiac arrhythmia.