BackgroundRecognition of MetS in type two diabetic patients is important in starting the appropriate preventive and therapeutic measures. The commonly used definitions of MetS have similarities and discrepancies. Different definitions defined metabolic syndrome differently. IDF, WHO, NCEP-ATP III, and the harmonized definitions were used frequently to determine the prevalence of metabolic syndrome.ObjectivesThis study was aimed to investigate the prevalence of MetS and its associated factors among patients with type 2 Diabetes Mellitus using four definitions and to identify the concordance and the difference of these four definitions.MethodsA cross-sectional study was conducted from February 28 to May 30/2017 at Hawassa university comprehensive specialized hospital. The study involved 314 study participants selected by simple random sampling technique. Logistic regression was used to determine associated factors of metabolic syndrome, and kappa statistics was used to determine the concordance between different definitions of metabolic syndrome. In any cases, a p-value of <0.05 was considered to be statistically significant.ResultThe prevalence of metabolic syndrome according to IDF, WHO, harmonized, and NCEP-ATP III diagnostic criteria was 59.9%, 31.2%, 65.6%, and 70.1%, respectively. Our study found the maximum agreement between IDF and NCEP criteria (K=0.54, P<0.001) and IDF and Harmonized(K=0.65, P<0.001). Uric acid level was associated factor of metabolic syndrome by all the four definitions, and total cholesterol was associated factors by the three definitions.ConclusionThe prevalence of metabolic syndrome varies based on the definition used and the highest prevalence of MetS was observed with NCEP-ATP III and the different types of criteria do not always diagnose the same group of individuals.