The company's popularity in Nigeria, where mobile phone use is growing at a breakneck pace, pushed profits for the six months to September up 92% to 60.9 cents a share (6.62 US cents; 4.28 pence).
Nor was MTN put off by the chaos gripping parts of the north of the country, saying it remained confident that its performance would continue to improve.
Operations in Nigeria are already making a profit, of 421m rand, more than a year ahead of schedule.
On the up
MTN, whose chairman is former senior African National Congress politician Cyril Ramaphosa, is becoming one of the fastest-growing operators on the continent.
As well as Nigeria, where subscriber numbers have surged 86% since March to 609,000, the company has more than 5 million customers in Cameroon, Swaziland, Rwanda and Uganda, not to mention its home market in South Africa.
Phone networks in Africa are hobbled by years of underinvestment and corruption, not to mention the difficulties of laying valuable copper wire which rapidly becomes a target for thieves.
As a result, mobile networks have proved extremely popular.
Stake sale
The effect is to give companies like MTN a huge shot in the arm.
Its success in Nigeria means that it has chopped its funding requirements for the country from US$900m to $770m, with cash flow making up the remainder.
The results were "fantastic", said Rhys Summerton of Salomon Smith Barney, who had been expecting only a 50% rise in profits.
"South Africa was a little disappointing, but Nigeria is exceptional."
MTN shares shot up 11% on the Johannesburg Stock Exchange in response.
The company also took the opportunity to settle an outstanding stock ownership issue, announcing that the 18.7% stake controlled by state transport operator Transnet is to be sold to a company representing staff and management.
The new company, dubbed Newshelf 664, is intended to help empower the mainly black workforce.