Treatment of HIV infection with highly active antiretroviral therapy can induce metabolic complications and increase the risk of developing the metabolic syndrome (MS). The purpose of this study was to report the prevalence and the risk factors for MS in HIV-infected patients who started highly active antiretroviral therapy (HAART) after 2000. SYMET is a prospective, multicentric, cohort study evaluating the prevalence of MS in 269 patients who had received continuous HAART for 1 to 4 years up to September 2007. MS was defined according to the American Heart Association (AHA) and the National Heart, Lung, and Blood Institute (NHLBI) 2005 criteria. Cross-sectional assessment included clinical examination and fasting evaluation of metabolic, inflammatory, and oxidative parameters. Data were analyzed with Chi-square, Student, or Wilcoxon tests. Univariate and multivariate logistic regressions were performed to identify predictive factors for MS. The prevalence of MS was 18.2% after a median duration of HAART of 29.8 months. In multivariate analysis, predictive factors of MS were high non-HDL-cholesterol (OR=1.87; p<0.0001), high-sensitivity C-reactive protein levels (hsCRP) (OR=1.56; p=0.01), coinfection with hepatitis C virus (HCV) (OR=5.67; p=0.02), as well as age (OR=1.04; p=0.02) and duration of exposure to protease inhibitors (PI) (OR=1.03; p=0.02) or to abacavir (ABC) (OR=1.03; p=0.02). In this cohort of patients exposed to less than 4 years of HAART, MS prevalence was 18.2%. Older age, high hsCRP, HCV coinfection, and elevated non-HDL-cholesterol were risk factors for the MS. There was also a moderate significant association of increased risk of MS with cumulative PI and ABC exposure.