To assess the prevalence of metabolic syndrome (MetS) among students attending vocational secondary school (VSE). VSE provides practice-oriented education in which young people learn a specific occupation. Previously we reported VSE to be the type of education with the highest prevalence of overweight and obesity. All data were collected in a cross-sectional school-based survey. Subjects were recruited from a community sample of 869 adolescents in 14 secondary schools. In this total sample all components of the metabolic syndrome were assessed in a subgroup of 506 students. MetS was defined analogous to National Cholesterol Education Program: Adult Treatment Panel III criteria, with modifications for students under 19 years of age. In the subsample (n=506) 4.1% of the students had metabolic syndrome. There was a significant difference in the prevalence of metabolic syndrome among BMI categories (p<0.001). The prevalence of metabolic syndrome was higher in obese students (39.1%) than in overweight students (2.8%) and normal weight students (0.3%). Being overweight or obese substantially increases the risk for metabolic syndrome, even in an adolescent school population.