Jung Jae-sung (also Chung Jae-sung; Hangul: 정재성; Hanja: 鄭在成; ; 25 August 1982 – 9 March 2018) was a South Korean professional badminton player.
Jung was born in Jeonju, Jeollabuk-do. He started playing badminton at 7, at his local elementary school. He entered the South Korea national badminton team in 2001.
At the 2012 Summer Olympics in London, Jung won a bronze medal.
In 2000, Jung 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 Guangzhou, he won the mixed team bronze after his team lose 2–3 to China, and in Kyoto, he won the boys'doubles silver and boys' team bronze.
Jung died of a heart attack on 9 March 2018 in Seoul at the age of 35.