SEOUL, Oct 7, 2012 (AFP) - The Asian Tour honorary member will donate his total winnings of US$118,875 to his KJ Choi Foundation, as he did following with his victory 12 months ago.
Choi scored a winning total of 15-under-par 269.
"I've always said that this tournament is all about giving back to the community and that's what I'm going to do with my winnings. I'll never be where I am today if not for golf and the great support from everyone," said Choi.
South Korea's Bae Sang-Moon, who was piling the pressure on Choi until a bogey-six on the 14th hole, had to settle for a share of second place with compatriot Jang Dong-Kyu on 271.
Korea's Kim Dae-Hyun, who shared the third round lead with Choi, signed for a 71 to take fourth place.
Australia's Scott Hend and seven-time Asian Tour winner Charlie Wi of Korea took a share of fifth place after they closed with matching 70s for a 274 total.
Thailand's Chinnarat Phadungsil's putting touch deserted him on the final day and he finished in seventh place, six shots back of Choi at the US$750,000 event which is jointly sanctioned by the Asian Tour and Korean Golf Tour.
After heavy fog seriously delayed play over the last two days, Choi had to return in the morning to complete his remaining nine holes for his third round.
He was still trying to find the rhythm in his game as he marked his inward-nine with one bogey and one birdie.
"I was starting to warm up when I came back in the morning to complete my third round. But once I got through those nine holes, three key elements came back into my game -- see, feel and trust," said Choi.
After taking a 15-minute break between rounds, Choi came out strongly with two birdies in his opening four holes.
He dropped a shot on the ninth but answered back with a hat-trick of birdies starting from the 11th hole.
Choi then parred the rest of his holes coming home to seal his sixth Asian Tour victory.
Leading scores after the fourth round at the CJ Invitational on Sunday (par 71):
269 - K.J. Choi (KOR) 69-65-68-67
271 - Jang Dong-Kyu (KOR) 68-71-65-67, Bae Sang-Moon (KOR) 69-68-66-68
273 - Kim Dae-Hyun (KOR) 71-65-66-71
274 - Scott Hend (AUS) 69-69-66-70, Charlie Wi (KOR) 67-70-67-70
275 - Chinnarat Phadungsil (THA) 68-64-71-72
276 - Arnond Vonganij (THA) 70-70-68-68