The largest-ever survey of fee-paying parents shows they most value schools which encourage good behaviour, firm discipline and individual attention.
By contrast, league-table performance came 33rd on a list of 37 desirable features and a school's religious attitude and social mix were also low priorities.
Neil Kern, head of the Durham School, where boarding costs pound;5,063 a term, said: "I agree with parents. It is cause and effect.
"If pupils are happy and disciplined they are going to enjoy their academic work, achieve their potential and maximise the league-table position."
More than 5,500 parents, representing nearly 13,000 children, responded to the Parent Profiles survey conducted by marketing consultants RSAcademics in September. More than two-thirds believed good exam results were essential to future success but only one in four judged a school by its results.
Generally speaking they had a poor opinion of state schools, most believing they were "getting worse".
Less than one-fifth would send their child to a good state school. There were regional differences, too. Parents in London considered smart dress a priority and valued ethnic diversity more than those in the south and east of England. Northerners put more emphasis on exam results and league tables.
This is the first survey to catalogue independent school parents' ethnic background. It showed that 94 per cent of parents are white and less than 1 per cent are black. Parents who did not attend private school themselves (41 per cent) were more likely to value a broad range of social background among pupils.
Men and women also had different educational values, with mothers caring more about behaviour and personal attention and fathers focusing on academic excellence, competition and sport.
Dick Davison, joint director of the Independent Schools Council, said:
"Independent schools pride themselves on the fact that they are not just exam factories and academic hot-houses. They are about developing the whole individual within a community."
But another survey, conducted by education publisher LCP this week, showed most people believe teachers have little more moral and spiritual influence on pupils than their friends or the media.
While three-quarters of respondents, from a variety of backgrounds, thought children should receive moral guidance at school, one-third thought schools were failing to meet this need.
Of the 1,000 people surveyed, only 11 per cent considered teachers the most influential factor. Most adults ranked parents as the most important and young people cited their friends.