Since turning pro in 1994, he has won more than twenty professional golf tournaments worldwide, including eight on the PGA Tour.

Choi won the first AT&T National hosted by Tiger Woods at the Congressional Country Club in Bethesda, Maryland.

After his 7th PGA Tour victory at the 2008 Sony Open in Hawaii, Choi donated $320,000 of his earnings to the victims' families of a warehouse fire in Seoul, South Korea, which killed over forty people.

Choi won his fourth title on the Asian Tour in Malaysia in 2009 at the Iskandar Johor Open, which was reduced to 3 rounds due to inclement weather.

[9] Following his win, Choi donated $200,000 to help victims of the tornadoes that ravaged the southeastern United States in April.

This was notable because it was the first time in Choi's PGA Tour career that he did not convert a 54-hole lead or co-lead into a win.

Choi continued his good early season from at the Northern Trust Open where he finished in a tie for fifth, despite holding the co-lead during the final round.

[11] In November 2022, Choi visited Vietnam to co-design Amber Hills Golf & Resort, Rock Valley Course with golf architect Paul Albanese in Bac Giang province near Hanoi[12] At the 2024 Senior Open at Carnoustie Golf Links in Carnoustie, Angus, Scotland, in July 2024, Choi kept the lead he held after both the second and third round and won the tournament, becoming the first South Korean player to win a Senior Major Championship, men or women.

He currently resides in Southlake, Texas, near fellow South Korean PGA Tour player Yang Yong-eun.

[17] PGA Tour playoff record (1–0) *Note: The 1999 Kirin Open was shortened to 54 holes due to rain.

QF, R16, R32, R64 = Round in which player lost in match play "T" = Tied Note that the HSBC Champions did not become a WGC event until 2009.