Abstract: Objective To conduct a health economic evaluation of five prenatal screening and diagnostic strategies for Down syndrome(DS) in China from a social perspective so as to provide evidence for health policy making.Methods Seven provinces were selected through convenience sampling. In each province, a secondary or tertiary hospital providing prenatal screening or diagnostic services was chosen as research site. The sample size of pregnant women was 7 200. Based on field investigation and literature review,five DS prenatal screening and diagnostic strategies were established. The decision tree model was used to conduct cost-effectiveness analysis and cost-benefit analysis. The direct medical cost was calculated through institutional questionnaires, and the direct nonmedical and indirect costs through questionnaire survey from pregnant women. The outcome indicator was the number of DS fetuses prevented, and the safety indicator was the number of abortions of normal fetuses divided by the number of DS fetuses prevented.Results The effectiveness of the full non-invasive prenatal testing(NIPT) screening strategy(providing NIPT for all pregnant women, then high-risk women undergoing prenatal diagnosis) was the best, with the DS avoidance rate being 69. 86%. The economic value of conditional NIPT screening strategy was the highest(providing NIPT for pregnant women ≥35-year-old, then high-risk women undergoing prenatal diagnosis; providing traditional maternal serum screening for women < 35-year-old, then high-risk women undergoing NIPT and prenatal diagnosis). This strategy had the lowest cost-effectiveness ratio(908 500 RMB per person), and the highest benefit-cost ratio(2. 79 RMB).Conclusion Compared with other strategies, the economic value of conditional NIPT screening strategy is the best. The full NIPT screening strategy remains costly at current NIPT prices. And the current national strategy may lead to unnecessary prenatal diagnosis.