Objective: Systematically review the value of second-trimester triple serum tests screening for Down's syndrome by using meta analysis. Method: The literature on PubMed, Journal of Medicine Library, CNKI, Web of Knowledge from January 2000 to April 2014 concerning second-trimester Down's syndrome screening was retrieved by computer or by hand. The literature was evaluated based on the QUADAS quality evaluation standard. The basic fourfold table data were extracted from the literature. Statistical analysis was conducted by using SPSS and Meta-Disc1.4. Results: Altogether 166 related articles were retrieved. According to the standard of literature selection and QUADAS quality evaluation, eventually 14 articles were brought into research. The meta analysis results of second-trimester triple serum tests screening for Down's syndrome were as follows: the sensitivity was 77%, the specificity was 93%, + LR was 13.92,-LR was 0.26, DOR was 40.82, the AUC of SROC was 0.9133, and Q*= 0.8458. In addition, the results of subgroup analyses based on age showed that the pooled sensitivity of high age group is higher than low age group, which indicated that the second-trimester serum triple serum tests screening for Down's syndrome could achieve better results for advanced maternal age. Conclusion: The second-trimester triple serum tests screening for Down's syndrome had a certain sensitivity and specificity, but for the regions with good medical and health care, they could consider increasing the serum screening indexes or adding ultrasound screening method so as to further improve the detection rate of Down's syndrome children and reduce the false-positive rate.