Hong Kong is a stronghold for traditional marriage and family values, with up to 75 per cent of parents holding negative views on gay-rights issues, research by a conservative Christian group indicates.
But the Society for Truth and Light said a more liberal trend was noted among younger parents which could eventually lead to conflict with traditional values.
The survey was called into question by a gay-advocacy group which said the society might have used biased questions to get the result it wanted.
The society's Centre for Life and Ethics Studies interviewed 2,096 parents from 12 kindergartens and primary and secondary schools by questionnaire between August and February.
It found that 60 per cent to 75 per cent of respondents did not want Hong Kong to allow same-sex marriage or adoption, same-sex couples to use artificial insemination or surrogacy, or partners to enjoy benefits "as if they were married".
"At the moment, many parents still see traditional marriage as very important," the centre's research officer, Michael Chan Wing-ho, said. "But we also see a trend of younger parents tending to be more open and agree with political requests by the gay rights movement. We can expect inevitable conflicts between them and traditional values."
About 60 per cent of respondents were atheists and 22 per cent Christians; 70 per cent were secondary-school graduates and 23 per cent had received higher education.
More than 72 per cent disagreed with a suggestion children should read books describing homosexual relationships as "normal and beautiful".
A similar percentage felt that teachers had the right not to teach that "homosexual relationships are normal and beautiful".
Chan said that the education systems of Western countries gave homosexual values an equal status to heterosexual values.
But Hong Kong's government should make its education policies based on scientific data and "healthy family ethics", not "political correctness", Chan said.
Brian Leung Siu-fai, chief campaigner for gay-rights group Big Love Alliance, questioned how scientific the society and its research were.
He said the society still used conversion therapy, widely criticised as pseudo-scientific, in efforts to "treat" homosexuals so that they become heterosexuals.
He suspected it had used suggestive questions in the survey.
Leung said older people held discriminative views towards the lesbian, gay, bisexual and transgender community because their parents knew nothing about it, there were no books available on the topic and public figures rarely came out as gay or supported the community.
"The older generation should be re-educated, because their discriminative views could be handed on to the younger generation," he said.