Choi Kyung-Ju, also known as K. J. Choi is a South Korean professional golfer who currently plays on the PGA Tour. Since turning pro in 1994, he has won a total of eighteen professional golf tournaments worldwide, including eight on the PGA Tour, making him Asia's most successful golfer. His most notable victory came at the 2011 Players Championship. He has spent 40 weeks in the top-10 of the world rankings.

Choi Kyung-Ju was born in Wando, South Korea on 19th May 1970. Before taking up golf he was a competitive power lifter, being able to squat 350 pounds as a 95 pound 13 year-old teenager, thus aptly nicknamed "Tank" by South Koreans. Choi turned professional in 1994.

Choi began his career on the Asian Tour, where he picked up his first professional wins at the 1996 Korean Open and the Japan Golf Tour, where he won twice in 1999. He qualified for membership of the PGA Tour by finishing joint 35th at the 1999 qualifying tournament and was the first Korean to earn a PGA Tour card.

In his rookie season in 2000 Choi finished 134th on the money list and had to requalify. However, since 2001 he has been a consistent performer on the tour. In 2002 he became the first Korean to win on the PGA Tour at the Compaq Classic of New Orleans, and followed this up with another win at the Tampa Bay Classic in the same year. In 2003 he won the Linde German Masters on the European Tour.

In 2005 Choi won the Chrysler Classic of Greensboro followed by the Chrysler Classic of Greensboro in 2006.

In June 2007 Choi won Jack Nicklaus's Memorial Tournament. During the tournament, he mentioned on CBS that he read Jack Nicklaus's book "Golf My Way" early in his golf career, which helped him become the golfer he is today. The following month he won the first AT&T National, hosted by Tiger Woods at the Congressional Country Club in Bethesda, Maryland. The trophy is a small replica of the United States Capitol building in Washington, DC