Nationally, black pupils were at a 3.4-times greater risk of expulsion that white children in 1996/97. But in some areas, including Trafford, Surrey, Essex and Sutton, that risk ran into double figures.
The Commission for Racial Equality said the figures were 'extraordinary'. It would consider using its legal powers to investigate authorities which such differences.
A spokeswoman for the department of the environment, transport and the regions said that the department had written to 50 authorities with disproportionately high ethnic minority exclusion rates emphasising the need to set targets for reductions as part of their behaviour support plans.
Asian pupils are less likely to be excluded than white children except in some areas such as Bolton and Bury, where rates for Pakistani children were about double the national average.
The worst regions were Merseyside and the south-west, where rates were seven to nearly 10 times higher for black pupils. Even in London, where most boroughs have large ethnic minority populations, the exlcusion rates varied significantly.
Muriel McIntosh, Sutton LBC's assistant director of education, said the number of ethnic minority children excluded were very small, giving a statistically distorted picture. She said Sutton takes exclusions extremely seriously.
Mike Barnett, a spokesman for Essex CC, said figures for 1997/98 showed non-white pupils were still at a higher risk, but less than in 1996/97.