Abstract: Objective To explore time trends of infection and behavior change related to human immunodeficiency virus/acquired immunodeficiency syndrome(HIV/AIDS),syphilis,and hepatitis C virus(HCV)among pregnant women in Liaoning province.Methods Cross-sectional surveys,including questionnaire survey and venous blood specimen testing,were conducted among pregnant women in 15 sentinel AIDS surveillance sites from 2010 to 2014.Results For the pregnant women surveyed during the period,the demographic distribution was not significantly changed;some of the pregnant women reported drug using history,but the prevalence of drug use maintained at a low level.The awareness rate of HIV/AIDS related knowledge increased from 77.0% in 2010 to 92.9% in 2014 among the pregnant women(P_trend<0.001).During the period,only two HIV positive cases were detected in 2011 and 2012 but the prevalence of syphilis increased from 0.37% in 2010 to 0.52% in 2014(P_trend<0.05).The prevalence of HCV was not significantly changed,with a fluctuation range between 0.15% and 0.42%(P_trend>0.05).Conclusion HIV prevalence among pregnant women maintained at a low level in Liaoning province.However,the prevalence of syphilis increased from 2010 to 2014.