The number of complaints about homophobia within the police has risen by almost a quarter, according to the Gay Police Association.
The Gay Police Association said calls to its helpline were increasing
The association said it received 350 calls to its helpline last year, compared with 260 the year before.
It estimated that there were about 7,000 homophobic incidents among police last year, but intimidated officers were reluctant to report them.
The police said "any form of homophobia has no place in the police".
The Gay Police Association said it was aware of colleagues refusing to serve with gay officers and quoting sections of the Bible at them on parade grounds.
Some officers have used legislation designed to protect religious freedoms to justify their actions, saying that they found homosexuality incompatible with their beliefs.
The Association of Chief Police Officers said it was aware of the concerns and has drawn up new guidance for senior officers to make it clear that discrimination cannot be justified on religious grounds.
Freedom of expression
Chairman of the Gay Police Association Paul Cahill said: "We've had officers refusing to work with gay officers but also slightly more sinister expressions of homophobia.
"We had situations where colleagues would come in to work and on parade would openly state their religious opposition to homosexuality and would even quote sections of the Bible. [This was] completely out of context with being at work and on parade.
"Many gay officers quite rightly felt that was an attempt to intimidate or harass them.
"But the officers behaving in that way would say 'we were asserting our right to freedom of religious expression' - albeit that it was questionable in the context in which it was raised, the timing and the manner in which it was raised."
Mr Cahill said some officers were using legislation promoting tolerance to be "openly homophobic and get away with it on the grounds they are entitled to under law - albeit that the law doesn't go that far."
'Crossing the line'
ACPO's lead officer on sexual orientation, Lancashire Police deputy chief constable Mike Cunningham, said he was aware of the concerns raised by the Gay Police Association.
"We are actively encouraging people to report racism, homophobia, anything to do with any particular minority with vulnerability.
"One of the problems with that is that sometimes the number of complaints actually goes up. That's not a cause for comfort and I'm not sitting here in anyway complacent," he said.
"Any form of homophobia has no place in the police. People with all religious beliefs also have a right to hold a religious belief. Where that crosses the line is when it infringes on the rights of other individuals with whom they are working.
"That sometimes is a complicated matter for managers to deal with and I'm seeking to provide guidance to help them work through that," he added.