Objective To explore the awareness and behavior of acquired immunodeficiency syndrome (AIDS) among female sex workers in Shanghai. Methods Multi-stage cluster random sampling method was adopted to obtain a random sample of five districts in Shanghai, then two communities of each district were randomly selected, and a total of 324 female sex workers from 88 massage parlors and hair salons explicitly providing sexual services completed a questionnaire survey and interview. Results The correct answer rate of AIDS-related knowledge was 60.8%, which was higher in female sex workers from urban area than that in those from rural area （P<0.05）. 29.5% of female sex workers had commercial sexual services without condom use for the request from guests, and 46.3% experienced condom slip off or breakage during commercial sexual services. Female sex workers from suburban area had more high-risk behaviors than those from urban area in oral and anal sex (P<0.05). Conclusion AIDS-related education should be strengthened to reduce high-risk behaviors among female sex workers in small entertainment venues of Shanghai, and particular attention should be paid to those from suburban area.