Former Chelsea and Celtic defender Paul Elliott said that he has known 12 top players who are gay.
Elliott, 44, revealed that they are reluctant to come out because they fear negative reactions.
The ex-central defender, who now advises the Equality and Human Rights Commission in the UK, was speaking at 'Homophobia – Football's Final Taboo' – a forum organised by the Kick It Out campaign and hosted by the English Football Association at its Soho Square headquarters in London.
BBC commentator Bob Ballard, who chaired the event, criticised the FA and Chelsea for allowing the appointment of Phil Scolari as Chelsea manager.
Brazilian Scolari had said that he would never have a gay player on his team, which is against the FA's equal treatment rules.
Accusing the FA of double standards, Ballard said that if Scolari had said he would kick out black or Jewish players he would have never been appointed at Chelsea.
Another speaker, gay human rights campaigner Peter Tatchell, said:
'The Football Association has great equality policies on paper but it often fails to put them into practice. It's time to turn the FA's opposition to anti-gay prejudice into action and give homophobia the boot.'
The issue of homophobia in football has been bought to head by the recent anti-gay abuse directed against Portsmouth's star player and England International, Sol Campbell.
with a wave of homophobic chants by Spurs' fans at the Portsmouth v Tottenham match at Fratton Park in September.