In 1993, Kim won the USTA National Boys' 16 Indoor Doubles Championship with Michael Russell.

[2] In 1995, he lost to Russell in the finals of the USTA National Boys’ 18 Clay Court Championships.

[1] Kim reached the second round in singles and the quarterfinals in doubles with Russell at the 1995 Australian Open Junior Championships.

[1] At the 1996 USTA National Boys’ 18 Championships, he lost in the doubles final with Russell to Bob and Mike Bryan.

[1] Kim reached the third round of the 2005 Australian Open, and won 9 Challenger titles in his career.