In 2021, Zuma was released from prison less than eight weeks after beginning a 15-month sentence for contempt of court. That came after he refused to testify in an anti-corruption inquiry conducted while he was in office.
Zuma’s medical parole was granted by the prison service, led by Arthur Fraser, an ally of the former president.
It was not immediately clear after the ruling Thursday whether the former president’s return to prison was imminent.
More than 300 people died in riots sparked by Zuma’s arrest.