The figures, obtained by Don Foster, Liberal Democrat education spokesman, also appear to show only a small variation between local authorities on the average overall attainments for English.
But within these variations, based on key stage 2 scores for 1997, the biggest gaps are between reading and writing attainments - and especially between the genders in writing.
They also show boys are twice as likely to reach level 4 in writing in some authorities compared to others.
Don Foster, who obtained the figures by means of a parliamentary question, said: "The Government's targets for English are meaningless unless separate targets are set for reading and for writing and for girls and boys. It is crazy that local authorities were not given the data I have received. This data is essential for setting targets."
The Government has pledged that 80 per cent of 11-year-olds will reach level 4 in English-which includes both reading and writing - by 2002. In 1997, 63 per cent of pupils hit the overall target, but while 67 per cent scored level 4 and above in reading only 53 per cent did so in writing.
Comparison by gender shows a gap of 18 percentage points in writing, with 62 per cent of girls reaching level 4 but only 44 per cent of boys. In reading there was a 9 point difference.
The gender gap also varies by local authority. In South Gloucestershire there was gender gap of 23 percentage points in writing, in Leicestershire and Cornwall a 22 point gap and in Dudley, Sandwell, Rotherham and Wakefield a difference of 20 points.
Mr Foster said the writing scores and gender gap were evidence of the need for a curriculum for early years - the Liberal Democrats proposed "foundation key stage" - and formal teaching from the age of six. "Countries which follow this pattern do not have such disparities between boys and girls," he said.
The figures also show that the average scores for local education authorities are contained within a narrow band, said Mr Foster. "They suggest that the variation in standards between authorities is not as wide as has been claimed."
A spokesman for the Government said: "We're satisfied that our literacy strategy, as it stands, ensures that we will meet our targets - so that youngsters can both read and write effectively."