Objective To study the difference between the metabolic syndrome(MS)diagnosis made with International Diabetes Federation(IDF)worldwide definition and the Adult Treatment Panel Ⅲ (ATPⅢ)of National Cholesterol Education Program(NCEP).Methods Cross-sectional study and descriptive study were used.Results There were 1328 MS patients diagnosed with IDF and 1527 MS patients diagnosed with ATPⅢ.There were 199 MS patients diagnosed with ATPⅢbut not with IDF and these MS patients all had 3-4 risk factors.According to the abnormality of glucose.blood pressure and lipid regulation stated in ATPⅢ criteria.759 more patients were diagnosed as MS than with IDF criteria.Conclusions MS diagnosed with ATP Ⅲ criteria iS more objective than with IDF criteria and ATPⅢ criteria has more space for further theoretical study.