Some admissions tutors made jokes about Asian candidates' surnames, while others made suggestive comments to female candidates, according to a survey of 21,000 applicants in 270 independent schools.
Some candidates have had to wait for up to five hours for interviews; interviewers were rude and aggressive; and students applying for a course in modern Greek were even questioned questioned in French.
The admissions procedure was a "lottery" for one in ten pupils because universities interview so few candidates. The heads said university admissions worked well for most pupils, but that most schools did experience some problems.
Leaders of the Headmasters' and Headmistresses' Conference of Public Schools and the Girls' Schools Association called for a fairer admissions system in which candidates would apply after they received their A-level results. At present, most pupils apply in the autumn before their A-levels for entry the following September.
The heads said that good candidates from six out of ten independent schools were being rejected without interviews because universities had to deal with so many applicants. The subjects most affected were medicine and English, where there are many more applicants than places.
Nearly a third of the schools complained of poor interviewing tactics, including long waits, constant interruptions and interviews which lasted only three or four minutes although the candidates had travelled hundreds of miles.
One in five schools reported examples of prejudice of some kind. In one interview of a girl applying for engineering, admissions tutors made jokes about women in engineering.
There were 17 reports of prejudice against independent schools, nine of them at Oxford and Cambridge. Around half the entrants to Oxford and Cambridge come from fee- paying schools.
Janet Lawley, head of Bury Grammar School for Girls and co-chairman of the working group on university admissions, said: "There are small numbers of examples of apparent prejudice where students have been questioned about their privileged background."
Tony Evans, chairman of the Headmasters' Conference said: "It may well be that some admissions tutors are trying to redress what they perceive as an existing imbalance towards pupils from independent schools. Many pupils from our schools come from backgrounds which are very far from privileged."
In medicine, possible prejudice was reported against a Spanish girl and against Asian and Hong Kong pupils and against those who may decide not to practise in this country.
One Catholic school felt that Oxford and Cambridge showed some prejudice towards Roman Catholics.
Dr Philip Cheshire, head of Warwick School and co-chairman of the working party, said most of the problems identified by the survey were encountered by state as well as independent school candidates.
Around 40 per cent of schools reported delays in universities' response to candidates who applied in good time. Delays were most common in English and medicine and for those who also applied to Oxbridge.
One boy who inquired why a reply to his application had been delayed was told: "What do you expect when your name begins with W?"
The heads argue that if students applied after they received their A- level results, the number of applications would be reduced because they would apply only for courses for which they had the right grades. At present, they apply for six colleges or universities on the basis of their predicted results.
Vice-chancellors are considering a two-tier application system, with some candidates applying before their A-levels and some after results come out.Reuse content