Objective: The aim of this study was to determine the prevalence of metabolic syndrome and its components among the young adult ages in İzmir, Turkey. Methods: A population-based cross-sectional study was held including 885 subjects aged between 20 to 39 years from 45 primary health care centres in Konak, which is the biggest urban area in İzmir. A stratified sampling method was used to select the participants of 318 males and 567 females. In the study, metabolic syndrome was classified according to NCEP ATP III criterion on the basis of metabolic risk factors evaluated between December 2001 and April 2002. Results: The crude prevalence of metabolic syndrome (having three or more of the metabolic risk factors) was 3.6% among 20 and 29 years old men and 19.6% among 30 and 39 years old men and the increase by age was significant (p<0.001). The results were similar in women and the crude prevalence of metabolic syndrome increased significantly from 7.5 % in 20 and 29 years old women to 24 % in 30 and 39 years old women (p<0.001). With regard to the highest prevalences of the first three metabolic risk factors, hypertriglyceridemia, low HDL-cholesterol and high blood pressure, the age-adjusted prevalence of the metabolic syndrome was significantly higher in women than in men and all subjects (15% vs 10.2% vs 13.6%, p<0.01) respectively. Conclusion: This study revealed that the prevalence of metabolic syndrome was extremely high between young adults in urban areas and the most prevalent components of the metabolic syndrome were found to be high triglycerides, low HDL cholesterol, high blood pressure, abdominal obesity and high fasting glucose, respectively