ObjectiveTo survey the knowledge, attitude and behavior about HIV/AIDS among men who have sex with men (MSM) in the main districts of Chongqing and to analyze the current status and demand on HIV/AIDS control in the districts. MethodsQuestionnaire survey was conducted among MSM, and qualitative interviews of MSM and some key informants, including the centers for disease control and prevention(CDC) staff, volunteers and the owners of bars or public bathrooms were done. ResultsAbout 80% of MSM were younger than 30 years old and were unmarried. More than half of MSM had college degree or above. Most of them were students, office staff and entertainment staff, and about 25% of them were bisexual. Television and newspapers were the main pathways to obtain knowledge on HIV/AIDS; friends, free publicity materials, internet and consulting services were also ways to obtain related knowledge. It was found that in the recent six months, 6.5%(50/772) of MSM sold and 3.9%(30/772) bought sexual services, and about 17.1%(132/772) MSM had sex with women in the recent six months. The rates of condom use among MSM when having sex with men and women at every intercourse were 41.9%(271/647) and 29.5%(39/132), respectively. And 82.0%(633/772) of them had intervention service. MSM suggested that their privacy should be fully protected during the intervention, more attractive publicity materials should be provided, and more knowledge was needed on other sex transmitted diseases; the intervention ways should be diversified; and they needed the consultation of professionals. The volunteers required more training and independent offices. The owners of entertainment argued that more efforts should be made to encourage the entertainment workers to promote intervention. ConclusionMSM in the main district of Chongqing have many high risk factors of HIV/AIDS. Though various interventions have been given and some achievement has been made, more efforts are needed to protect the privacy of MSM population and to improve the intervention. And efforts should also be made to promote the initiation of the volunteers, entertainment owners and staff.