Many are feared dead. Reporters saw rescue workers and police gathering body parts.
The blast ripped a hole 4 feet deep (1.2 metres) in the ground of Nyanya Motor Park about 16 kilometres from the city center and destroyed more than 30 vehicles, causing secondary explosions as their fuel tanks ignited and burned.
There was no official comment or an immediate claim for today's explosion though bus stations are a favored target of Nigeria's Islamic extremists.
The Boko Haram terrorist network last attacked the capital in 2011 when it claimed a suicide bombing by two explosives-laden cars that drove into the lobby of the United Nations office building in Abuja. It killed at least 21 people and wounded 60.
The militants are blamed for attacks in northeast Nigeria that have killed more than 50 people in the past five days, including eight teachers living at a boarding school that had been closed because of frequent attacks on schools in which hundreds of students have died.
Its mission is to force an Islamic state on Nigeria, Africa's most populous nation of some 170 million people divided almost equally between Muslims living mainly in the north and Christians in the south.
The military has claimed that it has the extremists on the run with near-daily air bombardments and ground assaults on hideouts in forests and mountain caves along the border with Cameroon.
