[2] Kwon qualified for two swimming events, as South Korea's youngest female swimmer (aged 15), at the 2004 Summer Olympics in Athens.

She eclipsed FINA B-standard entry times of 8:56.56 (800 m freestyle) and 2:11.59 (200 m butterfly) from the Dong-A Swimming Tournament in Seoul.

[3][4][5] In the 200 m butterfly, Kwon challenged seven other swimmers on the second heat, including top medal favorite Éva Risztov of Hungary.

[6][7] In her second event, 800 m freestyle, Kwon placed twenty-second overall on the morning prelims.

Swimming in heat one, she edged out fellow 15-year-old Jelena Petrova of Estonia to pick up a second seed by two tenths of a second (0.20) with a time of 9:01.42.