Pope Francis has appointed Gregory O'Kelly, the bishop of Port Pirie, the special administrator of Adelaide following the conviction of Archbishop Philip Wilson for covering up child sex crimes during the 1970s.
Bishop O'Kelly will assume administrative and executive authority in the archdiocese until any future decision of the Pope, the Australian Catholic Bishops Conference said in a statement.
"The Pope's intention is to provide stability for the people of the Archdiocese during these challenging times," Bishop O'Kelly said in a statement.
"Archbishop Wilson remains Archbishop of Adelaide but as Apostolic Administrator, I will exercise episcopal responsibilities in the archdiocese."
Wilson was found guilty in Newcastle Local Court on May 22 of failing to report to police the repeated abuse of two altar boys by pedophile priest James Fletcher in the NSW Hunter region.
He is the most senior Catholic official in the world to be charged with concealing child sexual abuse.
He stood aside following the court's decision and said if it became necessary at any point for him to resign, he would do so.
Wilson, who faces a maximum two years' jail, is expected to be sentenced this month.