Abstract: Objective To understand the incidence of birth defect in Yuzhong district, Chongqing municipality and provide evidence for the etiological research and prevention and control of birth defect as well as pregestational counsel service. Methods Birth detect surveillance was conducted among the infants in Yuzhong district during 2005-2012 according to National birth defect surveillance protocol and Chongqing maternal and child health surveillance protocol. Results A total of 592 birth defect cases were detected among 34 494 infants, the incidence of birth defect was 17.16. The first 3 birth defects were congenital heart disease, multi finger (toe) and cleft lip and palate. Conclusion Birth defect level and rank are closely related with prenatal screening and diagnosis. It is necessary to strengthen the health education, health care before marriage, maternal health care and improve prenatal screening and diagnosis to reduce the incidence of birth defect.