Abstract: Objective To systematically evaluate the correlation between adverse pregnancy outcomes and screening criteria for gestational diabetes mellitus by "one-step" and "two-step" methods. Methods Medline, Cochrane Controlled Register of Trials, EMBASE, CNKI and Wanfang databases were searched from time of foundation to August 2019. Randomized controlled trials(RCTs)diagnosing gestational diabetes mellitus(GDM)were collected by using "one-step" and "two-step" standards. The RevMan5.3 software was used to conduct a meta-analysis of maternal pregnancy outcome and perinatal outcome indicators, and to compare the effects of "one-step" and "two-step" standards on GDM detection rate, incidence of largest-age infants(LGA), incidence of neonatal hypoglycemia, NICU occupancy rate, neonatal birth weight and other pregnancy outcomes were compared. Results Eight RCTs literatures with 6 553 pregnant women were included in this study. Meta-analysis showed that when compared with the "two-step" method, the "one-step" method had a higher detection rate of GDM(P<0.001)and lower incidence rates of LGA(P=0.03), macrosomia(P=0.01), neonatal hypoglycemia(P<0.001), NICU occupancy rate(P=0.009)and neonatal birth weight(P=0.000 8). Conclusion Compared with "two-step" method, "one-step" method has a higher detection rate of GDM, and can reduce the incidence rates of LGA, macrosomia and neonatal hypoglycemia, NICU occupancy rate and neonatal birth weight as well as significantly improve perinatal outcomes.