Kim qualified for the women's 400 m freestyle, as South Korea's youngest swimmer (aged 15), at the 2012 Summer Olympics in London, by eclipsing a FINA B-standard entry time of 4:15.01 from the Dong-A Swimming Tournament in Ulsan.

[3] She challenged seven other swimmers on the second heat, including three-time Olympian Kristel Köbrich of Chile.

Kim finished the race in last place by nearly 25 seconds behind Singapore's Lynette Lim, posting the second-slowest time of 4:43.46.

Kim failed to advance to the final, as she placed thirty-fourth overall in the preliminary heats.

This biographical article related to a South Korean swimmer is a stub.