The 2014 champion began round four seven shots behind the overnight leader, but birdied the last to get to 17 under and pile the pressure on the South African.
Frittelli sent his second shot into the last over the hospitality tent and had to settle for a par, a closing 74 and a trip back up the 18th.
Levy found the fairway off the tee while Frittelli sent his drive right into a bunker but after the Frenchman found sand with his second, both men were left with birdie putts.
Frittelli missed his attempt and Levy rolled home from 15 feet to claim victory and a perfect birthday present for caddie Tom Ayling.
"That's an amazing feeling to be back in the winner's circle," said Levy.
"This means a lot because it was the first tournament I won on the European Tour. I won last year after a bad injury and to come back with the win was very tough for me. I'm really happy with what I did today.
"Happy birthday to my caddie because it's his birthday today and I think it's a really good present."