An Jae-sung

An Jae-sung (born 28 May 1985) is a retired South Korean tennis player.

An has a career high ATP singles ranking of 289 achieved on 14 April 2008. He also has a career high doubles ranking of 454 achieved on 18 August 2008.

Early life and career
An attended Konkuk University. While a student, he represented South Korea in tennis at the 2006 Asian Games in Doha, Qatar, where he and his teammates won a gold medal in the men's team event, thus securing an exemption from his mandatory military service.

An has been a member of the South Korea Davis Cup team from 2005 until 2008, competing in the World Group first round tie in 2008 against Germany.

In 2008, he captured his only ATP Challenger Tour doubles title in Moncton, Canada.

He retired in 2014, and now runs a tennis academy in Jeju.