Mediation effect of sexual communication on the relationship between safer sex self-efficacy and condom use was tested among 307 homosexually active migrant men, 376 heterosexually active migrant men, and 265 heterosexually active migrant women. The study found certain aspects of sexual communication mediated the effect of self-efficacy on condom use among the three samples. The findings underscored the importance of including components that promote safer sex self-efficacy and sexual communication in HIV prevention interventions for Chinese migrants.Social cognitive theory (SCT; Bandura, 1992) states that human behavior is the result of interactions among personal factors, environmental factors, and the behavior itself. Self-efficacy, an individual's confidence in performing a specific behavior, has been identified as one of the most salient personal factors that influence behavior.