Cardinal Orani João Tempesta was driving through the Brazilian capital on Monday night when he was robbed.
Rio Archdiocese spokesman Adionel Carlos da Cunha said the cardinal was on his way to a radio station with his photographer, a seminarian and a driver when the incident happened.
No one was hurt and it is reported that the thieves recognised the cardinal and apologised before stealing his mobile phone, ring, crucifix and pen, as well as the photographer's cameras.
Police later found the cardinal's possessions but not the camera.