Jo Hye-Jeong was first selected for the Japanese national volleyball team in 1970 while she was still in high school. The same year Jo was part of the squad that won silver at the Asian Games in Bangkok. Two years later South Korea finished fourth at the 1972 München Olympics after losing to their neighbours North Korea in the medal round. In 1974 she won another silver at the Asian Games, along with a bronze at the World Volleyball Championships. At the 1976 Montréal Olympics the South Korean team went one better than their previous performance to win bronze in a closely-fought contest against Hungary. Jo retired from volleyball in 1981 and became a coach at GS Caltex. She rounded off her career by having the honour of being the flagbearer for South Korea at the Opening Ceremony of the 1988 Seoul Olympics.