Known as the 'Blade Runner' because he runs with carbon fibre prosthetic running blades, the 25-year-old will run in his country's 4x400 metre relay team.
Pistorius failed to qualify for the 400m at the Games when he ran a quarter of a second too slow at the African championships in Benin last Friday.
But Wednesday's decision by his country's athletics authorities turned his despair to joy in five days.
He ran below the qualifying time of 45.30 seconds once in South Africa, but SASCOC -- South African Sport Confederation and Olympic Committee -- was adamant athletes had to qualify outside the country, too, to make the cut.
This followed a dismal performance at the Beijing Olympics, where 265 able-bodied South African athletes brought back only one medal and sparked national embarrassment.
Authorities are determined it won't happen again.
Multi Paralympic gold medalist Pistorius has already been chosen for his country's 65-strong paralympic team. Now he will become the first double amputee to compete in the able-bodied competition.
The Johannesburg-born runner had both legs amputated below the knee when he was 11 months old because of a congenital condition that meant he was born without fibulae -- lower leg bones.
This hardly hindered his sports activity when he grew up and performed with prostheses.
At first, Pistorius played contact sports at school, but when the sportsman fractured a knee playing rugby he took to track running, and has never looked back.
He was cleared four years ago to run against able-bodied athletes when the Court of Arbitration for Sport (CAS) overturned a ruling by the International Association of Athletics Federations (IAAF) that his blades gave him an unfair advantage.
Pistorius hired experts to do tests that proved the blades did the same work as normal feet.
The 25-year-old went on to win a silver medal as part of the 4x400m relay team at the 2011 World Championships in South Korean city Daegu.
Ever the adrenalin junky, his love of speed is reflected in a passion for motorbikes.
Four years ago he crashed his boat in a river south of Johannesburg, breaking two ribs, an eye socket and his jaw.
And as though his legs weren't exotic enough, he once owned two African white tigers, but sold them to a zoo in Canada when they became too big.
The Pretoria commerce student's unusual running gear and masculine physique have garnered him global popularity and drew millions of spectators at the Beijing Paralympics.
His ambition to perform in able-bodied events still draws criticism from peers, like 400m Olympic champion LaShawn Merritt from the United States.
But Pistorius has consistently insisted he deserved to be treated the same as an able-bodied athlete.
"The prosthetic legs I'm using, the cheetah, have been around since 1996 and I've had the exact same model, same shape since 2004 and nothing's changed on it," he told reporters.
SASCOC officials had hinted at wild cards for those who didn't qualify for London, and Pistorius' attraction and prestige in the able-bodied event have proved an irresistible temptation to a country hungry for glory.