The 34-year-old, whose ball carries led to affectionate chants of 'Beast' in stadia around the world, was a stand-out performer as the Boks beat England 32-12 to lift the Webb Ellis trophy in Yokohama on Saturday, the last of his 117 tests.
He won a number of scrum penalties on the loose-head side as South Africa dominated the set-piece to lay the platform for their third World Cup title.
"I am grateful for the opportunities afforded to me by many top coaches at the Springboks and the Sharks, and grateful to my numerous team mates in green and gold, and black and white, over the years," Zimbabwe-born Mtawarira said in a statement from South African Rugby.
"But most of all, to my wife Kuziva, and our two beautiful children, Talumba and Wangu, for sacrificing so much to allow me to chase my dreams. I really appreciate it immensely.
"I've been blessed to have been part of teams that achieved so much success over the years, and I have many memories to cherish forever, but I can honestly say that winning the Rugby World Cup is the perfect ending and cherry on top."
(Reporting by Nick Said; Editing by Christian Radnedge)