South African Andre Watson will referee Saturday's final, with Ed Morrison, of England and Paddy O'Brien of New Zealand running the line.
Watson, a professional referee is officiating at his first World Cup tournament.
The South African Rugby Union said Watson's appointed reflected credit on South African rugby.
"This is a great achievement for Andre," said SARFU chief executive officer
Riaan Oberholzer.
"It confirms his status as one of the top referees in world rugby. He has worked very hard at becoming better and better in recent years - and it has paid off.
"The South African rugby fraternity is very proud of his achievement. We acknowledge the sacrifices he has made to reach this goal, and wish him well for Saturday's game".
Australian Peter Marshall will referee the third-place playoff between South Africa v New Zealand on Thursday with his touch judges Wayne Erickson, also of Australia, and Jim Fleming of Scotland