"All four were remanded in custody yesterday (Friday) after having been charged the same day," said Michel Togue.
Two of them were also charged with "indecent behaviour involving a minor".
The lawyer said one of the accused "said he was arrested at his home on August 10" in the capital Yaounde after "somebody turned up and asked to see a ‘gay film’ in his company".
It was "obviously a set-up because police arrived to arrest him as they were watching the film", he added.
The three others were arrested when they visited him after his arrest.
Police were not available Saturday to comment on the arrests which take the number of those detained in less than a month to seven.
Three Cameroonian men were arrested at the end of last month after returning from a bar in Yaoundé. The two men detained for feminine appearance were tortured in police custody and charged under laws criminalising homosexuality. They were tried at the Court of First Instance in Ekounou, Yaoundé on 18 August.
Roger Jean-Claude Mbede was sentenced to 36 months in prison for homosexuality in May. He was also entrapped and then arrested by police. Amnesty International have classified him as a prisoner of conscience.
The Cameroonian government is preparing to reform its criminal code and may toughen laws criminalising homosexuality according to Alice Nkom, head of the Association pour la Défense de l’Homosexualité (ADEFHO). The age of consent for heterosexual couples in Cameroon is 16. The proposed laws would punish homosexual couples between the ages of 16 and 21 with eight years in prison for pedophilia.