Abstract： INTRODUCTION Gestational diabetes mellitus (GDM) was earlier defined as "hyperglycemia first recognized during pregnancy" and has more recently been described by American Diabetes Association (ADA) (2012) as diabetes diagnosed during pregnancy that is not clearly overt diabetes.[1] The hyperglycemia and adverse pregnancy outcomes study (HAPO) demonstrated that the risk of adverse maternal,fetal,and neonatal outcomes continuously increase as a function of maternal glycemia at 24-28 weeks,even within ranges previously considered normal for pregnancy.[2] After reviewing the results of the HAPO study,many international diabetes study groups,including the International Association of Diabetes and Pregnancy Study Groups and ADA have adopted the 75 g oral glucose tolerance test (OGTT) at 24-28 weeks as a screening and diagnostic test and defined new cut-off values for GDM diagnosis.The Ministry of Health of China published the criteria for GDM,that is the same as the ADA criteria on July 1,2011.World Health Organization (WHO) has recommended the 75 g OGTT with different cut-offvalues as a diagnostic test since 1999,changed its recommendation on 2013.In Hongkong and Yunnan province in China,most hospital adopted the WHO 1999 criteria,nevertheless,there is no evidence of multicenter and large sample to show that the GDM population within the same ethnic group diagnosed by the new WHO criteria matches those diagnosed by the old one and consistency between the two criteria has not been reported.Thus,we conducted this study to analyze the two criteria in Chinese pregnant women.