Abstract: Objective To establish a birth defect surveillance system covering the whole population, so as to carry out birth defect monitoring, and get a full view of the prevalence of birth defects in Hefei, Anhui.Methods The birth defect surveillance network and information management system was built based on maternal and child health network and information platform. Population monitoring was conducted in accordance with the national Birth Defect Population Monitoring Program. The surveillance results from 2018 to 2020 were analyzed.Results A birth defect monitoring system covering Hefei city including district, town and village was established. The coverage of the population was 100%. Perinatal omission rate, severe birth defect omission rate and report error rate was all lower than the requirement of national population monitoring program.The follow-up rates of perinatal infants were 96.50%, 95.01% and 96.80% respectively, and the incidence of birth defects were 22.75‰, 32.06‰ and 29.42‰ respectively from 2018 to 2020 in Hefei, Anhui. The incidence of birth defects in males(29.93‰) was higher than that in females(25.69‰), while this number in urban area(34.63‰) was higher than that in rural area(20.01‰). Top five birth defects were congenital heart disease, multiple fingers/toes, other outer ear deformities, microtia, and syndactylia in 2018, while they were congenital heart disease, multiple fingers/toes, hydrocele of testis, deputy ear, other outer ear deformities in 2019 and congenital heart disease, other outer ear deformities, deputy ear, multiple fingers/toes, hereditary metabolic disease in 2020.Conclusion The quality of birth defect monitoring in Hefei is high. The incidence of birth defects in Hefei should be further reduced.