Men who have sex with men and women (MSMW) are a potential bridge population for transmitting HIV to heterosexual women. This study assessed key characteristics of this subgroup of men who have sex with men (MSM) in China. Of 1141 eligible MSM, 45.6% reported bisexual behaviors. Besides marriage as a strong predictor (odds ratio: 23.90, 95% confidence interval: 14.29-39.98), older age (1.12, 1.10-1.15) and lower education (or no college education) (1.98, 1.52-2.59) were also independently associated with having ever had sex with women. MSMW reported higher proportions of alcohol drinking, heterosexual/bisexual orientation, and preference for an insertive role in anal sex than men who had sex with men only; but there was no statistically significant difference between two groups in prevalence of HIV and syphilis infections and in history of sexually transmitted infections. HIV prevention intervention programs should break the bridging role of HIV transmission in MSMW population.