Abstract: Objective To understand the factors influencing the utilization of voluntary counseling and testing (VCT) by female sex workers (FSWs) to improve the utilization of VCT. Methods The interview guide was developed based on the theories of Reasoned Action and Social Ecological Perspective. At least 2 FSWs from each type of recreation centers were selected to do face-to-face in-depth interview. Results Among 17 FSWs interviewed, 15 expressed their willingness to visit the clinic. The most common reasons for FSWs not utilizing VCT were limited understanding of HIV and VCT, low perceived risk for HIV infection, worrying about positive testing and its consequences, double stigmas from sex work and HIV infection, as well as low trust on medical system and the quality of VCT service. Conclusion Taking measures of comprehensive interventions including in-depth, long-term health education, free treatment and anti-stigma for FSWs can improve the utilization of VCT and control the spread of AIDS. This study was funded by the joint project of National Institute for Viral Disease Control and Prevention,Chinese Center for Disease Control and Prevention and National Institutes of Health In USA (No.RO3AI062276-01A1)