Girls consistently outperform boys
Five out of six poor white boys in England did not meet the government's target of at least five good GCSEs including English and maths this year.
This compares to 25% of black boys and 32% of Asian boys of similar backgrounds, the new figures show.
Only one group performed worse - Gypsy/Romany pupils on free school meals.
Schools minister Jim Knight said the groups where children were doing well often shared a belief in the "value of family and education".
He said the challenge was to raise aspirations and improve relations between home and school - and the government was working to do that.
As usual, girls outperformed boys in the 2008 GCSE results with 52% of girls getting five good GCSEs including English and maths, compared with 44% of boys.
The eight percentage point achievement gap between the genders is slightly lower than in 2007 - when it was nine percentage points.
The now established attainment gap between the poorest members of different ethnic groups has prompted some to call for extra resources to be targeted specifically at poor, white boys.
Currently, extra money has been passed to schools for teaching children from black and other ethnic minority groups.
They also get extra cash for teaching pupils on free school meals, whose parents will be claiming means-tested benefits.
However, when social background is disregarded, white boys still do significantly better than their black counterparts.
Some 47.3% of all white boys reach the government's benchmark compared with 37.3% of all black boys.
At the same time 49.9% of all Asian boys and 64.6% of all Chinese boys get five good GCSEs.
Liberal Democrat children's spokesman David Laws said: "Over half of poor Chinese boys achieve the five A*-C standard.
"Urgent questions must be asked about why white boys from similarly deprived backgrounds are falling behind.
"Ending entrenched disadvantage will take more than tinkering. We need a Pupil Premium to increase the per pupil funding of the poorest pupils to private school levels, allowing for more catch-up classes and additional support to give every child a chance."
Shadow schools minister Nick Gibb it was deeply worrying that the gap between the better off and disadvantaged was growing.
"A culture of low expectations and a lack of rigour are holding these pupils back.
"We need to ensure that schools in the most deprived areas are using the type of high-quality academic teaching which we know can drive up standards, with a focus on setting by ability and a strong behavioural policy," he said.