The 25-year-old from Cape Town received the title on Friday night at a gala function held at the ZAR night club in Sandton, Johannesburg, the Saturday Star reported.
"It feels amazing. It still hasn't hit me though," Fairbrother told the newspaper.
"I've been thinking about it and it's just so unreal. It's the best news I have ever received."
Fairbrother received a customised Playboy pendant worth R50 000 and would spend five days at the Playboy mansion in Los Angeles as part of her prize.
She also won an expensive watch and would feature as the cover girl for the March edition of Playboy, the newspaper reported.