She had been qualified for an international referee from 1997 to 2016. And she was active as an assistant referee in 50-odd international football games, including the 2008 FIFA U-17 Women's World Cup, the 13th Asian Women's Football Championships and the women's football event of the 17th Asian Games.

When interviewed by KCNA, Pak Yong Sun said that she would continue to make contribution to training of football reserves and development of football technique.