More than 100 million Nigerians, about 61 percent of the population, were living on less than $1 a day at the end of 2010, a government report says.
That's up from 51 percent in 2004, the Nigerian Bureau of Statistics said.
Those who can afford only essential food, clothing and shelter increased to about 61 percent of the population, up from 54.7 percent in 2004.
The bureau said poverty has worsened in the oil-rich African country despite economic growth, the Daily Trust reported.
"It remains a paradox ... that despite the fact that the Nigerian economy is growing, the proportion of Nigerians living in poverty is increasing every year," said Yemi Kale, the statistician general.
Northwest Nigeria had the highest poverty rate, at 70 percent, followed by the northeast, 69 percent, while the southwest and southeast had the lowest rates, at 49.8 percent.
Kale said poverty could worsen as a result of the recent economic crisis.