AngloGold said the incident occurred on Tuesday morning and immediately triggered a search and rescue effort.
After more than two days of effort by mine rescue teams in difficult geotechnical conditions, the missing worker has yet to be located.
Perenti Global confirmed the contractor was an employee of Underground Mining Alliance (UMA), a 70:30 joint venture between Perenti and Ghanaian contractor Rocksure.
UMA is working closely to support AngloGold Ashanti.
"Our thoughts are with the family, friends, and colleagues of the UMA team member at this difficult time," Perenti said.
All mining activity has been suspended.
Perenti does not expect the suspension to have a material impact on FY21 earnings.