Women academics earn, on average, Pounds 4,300 less than their male colleagues, according to figures released this week.
At the London Business School, the pay differential in 1997-98 topped Pounds 19,000, while women's average salaries were higher than men's in just two institutions out of 175: King Alfred's College, Winchester, and Glasgow School of Art.
The figures, compiled by university and college lecturers' union Natfhe from data released by the Higher Education Statistical Agency, show that differentials in Wales, Scotland and Northern Ireland are even worse than in England, averaging Pounds 5,000 or more.
They also reveal the extent of casualisation in the sector. Top of the list of institutions with high levels of non-permanent staff is the Royal College of Art, which employs no permanent academic staff.
Thames Valley University is bottom of the list, with only 1 per cent of staff on non-permanent contracts in 1997-98. TVU also has a relatively low - less than Pounds 1,000 - male/female wage differential.
University College London and the University of Leicester each have male/female wage differentials of more than Pounds 7,300, the highest of the non specialist institutions, and also have a high percentage of staff, more than 60 per cent, on non-permanent contracts.
Natfhe says that its recent survey of part-time academic staff shows that women make up a higher proportion of the part-time than full-time workforce and that conditions of employment are usually poorer than for full-time staff.
It is calling for all regular teaching staff, including hourly paid staff, to be employed on full-time equivalent contracts.
Saul Estrin, professor of economics and dean of faculty at the London Business School, said its women earned relatively low salaries because they tended to be in lower positions, but that this was expected to change. "We wish to raise the number of faculty who are women in all subject areas and at all grades," he said.
A spokesman for the University of Leicester said it employed a large number of non-permanent staff because it was a leading research university and many staff relied on non-permanent research grants. He said the disparity between male and female earnings was not surprising as Leicester was strong in medicine which tends to be male dominated.
Natfhe estimates that to end sex discrimination in pay, as recommended in the Bett report, would cost just under Pounds 182 million.
It would cost University College London alone more than Pounds 7 million and Cambridge nearly Pounds 5.8 million. Leicester would have to spend more than Pounds 3 million.
Tom Wilson, Natfhe's head of higher education, said: "We think these figures show there is endemic discrimination from top to bottom of the entire system." But Diana Warwick, chief executive of the Committee of Vice-Chancellors and Principals, said: "Universities take equal opportunities issues very seriously and are working hard to improve recruitment and promotion opportunities for women in academia."