Pat Sikes, of Sheffield University, concluded that "erotic charges" were common in schools, particularly as a result of good teaching "which provokes a positive and exciting response".
Her 25-year study stressed that exploitative relationships were wrong, but added that it was not always a case of teacher exploiting pupil, the Times Education Supplement reported.
Dr Sikes met her husband, David, at school when she was 14. He was 22, and a teacher. They declared their feelings two years later, when he left to take a job elsewhere. She said teacher-pupil affairs at her school in Leicestershire were neither uncommon, nor seen as sordid. The study found it was often pupils who initiated relationships and that most teachers and pupils knew of teachers and pupils who had married or were living together.
Her comments have angered children's charities, which have described her opinions as "misguided and bizarre at best". A spokesman for the NSPCC said that teachers had a unique relationship with their pupils that should never be abused.
Last month, a 25-year-old geography teacher was found guilty of abuse of trust after kissing a 15-year-old boy. An English teacher, 30, could go to jail for having a relationship with a 16-year-old boy.