Kim captured the world attention when he unexpectedly winning the gold medal in the mixed doubles event with Gil Young-ah at the 1996 Atlanta Summer Olympics.

[2] Despite their domination, the golden couple crashed in the second round against the Danish partnership of Jonas Rasmussen and Rikke Olsen at the 2004 Athens Olympics.

In the final, they rallied to upset their fellow Koreans Park Joo-bong and Ra Kyung-min 13–15, 15–4, 15–12 to win the gold medal.

Kim also competed in men's doubles with partner Yoo Yong-sung, but was surprisingly eliminated by Michael Søgaard & Henrik Svarrer of Denmark 15–11, 5–15, 18–15 in the first round of the event.

They won the semifinal against Eng Hian and Flandy Limpele of Indonesia 15–8, 15-2 and defeated fellow Koreans Lee Dong-soo and Yoo Yong-sung 15–11, 15–4 to win the gold medal.