The Lane legend will take on the role after being approached by Danny Jordaan, chief executive officer of the South African Football Association and head of the country's bidding committee for the right to stage the tournament.
It will be that extra special for 'Mabbsy' as his wife Kathy is from South Africa. Her family is based in Johannesburg and the Mabbutt family are annual visitors.
Gary, 16 years at the Lane, explained: "I've known Danny Jordan for a number of years. He's head of the South African 2010 bid committee.
"There was a lot of disappointment after they lost the 2006 bid to Germany.
"Danny asked if I would consider becoming an ambassador for South Africa because in the 2006 bid, England were also competing and obviously my allegiance was with England. In 2010 England aren't bidding and it will go to Africa.
"My wife is South African, her family are based in Johannesburg and we're out there every year for a few weeks seeing the family.
"When I'm out there I'm also involved in development works in sport and I also do a lot of work with Super Sports TV, their equivalent of Sky.
"So with those connections they asked if I would consider being an ambassador for the bid and I was more than happy to do so.
"It can't be a World Cup until it's gone to Africa and while there will be a number of countries competing, the likes of Nigeria, Morocco, Egypt, Libya, I just think South Africa will be the strongest.
"The country has already successfully hosted the Rugby World Cup and Cricket World Cup.
"It will be the most passionate World Cup in South Africa. The passion for the game is immense and I think it would be a huge lift for the country if it won the bid.
"Every time I go there I do a bit of work in the townships, I've been out there for the last few weeks around the England game.
"You visit these townships and all the youngsters know the English players and their love for the game is quite amazing. The passion is there and I believe South Africa is capable of putting on a memorable World Cup."
Gary Mabbutt has spoken of his pride in becoming an ambassador for South Africa's World Cup 2010 bid.