Interior minister Raymond Zephyrin Mboulou announced the results on national television at 3:30 AM local time following a tense weekend poll held under a communications blackout.
The official count gave Guy-Brice Parfait Kolelas 15 per cent of the vote and General Jean-Marie Michel Mokoko came in third with 14 per cent.
Yesterday, the two opposition candidates rejected partial results released by the national electoral commission, which gave the country's long-time ruler 67 per cent of votes.
The long-serving leader is accused by critics of rampant corruption and nepotism and of stifling democracy.
Authorities imposed a communications blackout during the vote to prevent opposition candidates from publishing their own results. A government source said they would remain suspended until after the official results were announced.