Aung competed only in the women's 50 m freestyle at the 2000 Summer Olympics in Sydney. She received a ticket from FINA, under a Universality program, without meeting an entry time. She participated in heat one against two other swimmers, 12-year-old Fatema Hameed Gerashi of Bahrain and Paula Barila Bolopa of Equatorial Guinea. Aung pulled away from a small field to an unexpected triumph in a new Burmese record of 26.80, finishing farther ahead of Gerashi, who was later disqualified from the race for a no false-start rule attempt, and Bolopa, who posted the event's slowest time in Olympic history (1:03.97). Aung's surprising reward was not enough to put her through to the semifinals, as she placed thirty-ninth overall out of 74 swimmers in the prelims.