Abstract: Objective: To investigate the awareness of mother-to-child transmission knowledge of syphilis in pregnant women and to provide references for prevention and control of mother-to-child transmission of syphilis among pregnant women.Methods: Totally 1274 pregnant women were recruited and investigated by a questionnaire about the awareness of mother-tochild transmission knowledge of syphilis. The participants consisted of 3 groups of pregnant women, including urban residents,rural residents, and transient population. Results: The overall awareness rate of syphilis prevention knowledge was 56.91%.The highest awareness rate of 72.72% was found in urban group, followed by 51.35% in rural group and 44.44% in transientpopulation. The three groups of pregnant women accessed to the knowledge mainly via radio, television, newspapers, books and the network. Conclusion: Among pregnant women, the knowledge related to mother-to-child transmission of syphilis is poor. We should take effective measures to prevent and control congenital syphilis by improving health care service quality before marriage and pregnancy and improving the clear understanding of syphilis knowledge among pregnant women.