Abstract: Objective To examine the situation of commercial sexual behavior and its influential factors among migrants in Shenzhen city for providing evidence for effective intervention.Methods A cross-sectional survey was conducted and 1 014 migrants were recruited with multistage sampling from Yantian,Luohu,Futian districts of Shenzhen from October 2006 to March 2007.Information was collected with a face-to-face questionnaire survey by trained interviewers.Results The proportion of subjects who had trading sex was 4.65%(38/817).There were 7.94%(27/340) of male subjects having commercial sexual behavior and 2.31%(11/477) of female having commercial sexual behavior.Multiple logistic regressions showed that gender,sex partner at debut were the possible influential factors for commercial sex.Compared with male,female had lower commercial sex(odds ratioOR=0.28,95% confidence intervalCI:0.13,0.63).The subjects with a non-spouse sex partner at debut had slightly frequent commercial sexual action(OR=2.26,95% CI:0.91,5.65),but the difference was not statistically significant(Wald χ²=2.96,P=0.081).Conclusion Male migrants have a higher occurrence of commercial sex compared with female migrants,whereas those who had a non-spouse sex partners at debut also had a higher commercial sexual behavior.More emphasis should be implemented on the advocacy for safe sex to reduce commercial sexual behavior,especially among male migrants.