Abstract: Objective The study was conducted to investigate the proprietors of entertainment places and prostitutes for the changes in their knowledge of, attitude to and behaviors associated with AIDS before and after the implementation of AIDS intervention, in order to analyze the intervention effects on both groups in the project. Methods The knowledge, attitude and behavior (KAP) surveys were conducted for the entertainment proprietors and prostitutes in the areas involved in the project before (505 proprietors and 503 prostitutes) and after (506 proprietors and 730 prostitutes) intervention, from which significant indicators were used for the comparative analysis of the results of the two surveys. Results The results showed an increased score among entertainment proprietors in relation to their knowledge of AIDS prevention from the baseline 57.9 to 86.1, while that score of prostitutes increased from 58.3 to 83.0. The results also suggested significant improvement of the proprietors' attitude towards HIV infected people and patients after intervention. Condom use rates of prostitutes in the last sexual activity with frequenters rose from 79.6% to 91.4%; and the proportion of prostitutes who had visited a public hospital increased from 51.6% to 65.1%. Conclusion After nearly two years of publicity and intervention, significant improvement was shown among the intervened population along with their AIDS-related knowledge, attitude and behaviors. However, long-term interventions and observation are still required to determine whether these changes among prostitutes can reduce the HIV infection rate and the vulnerability to HIV infection in this particular population.