Polycystic ovary syndrome (PCOS) is the most common endocrinopathy of reproductive-aged women that manifests itself with a variety of features. For this reason, three different diagnostic criteria have been introduced. For adults, the National Institutes of Health Conference (NIH) criteria, which consists of hyperandrogenism and oligo-anovulation, is the most widely used. Symptoms of PCOS usually start with puberty and may overlap with normal pubertal development. Hormonal fluctuations during this period make the diagnosis of PCOS more difficult. Until now, there is no validated diagnostic criteria for PCOS in adolescents. Although menstrual disorders and cosmetic problems are the most common complaints of adolescents with PCOS, patients should also be evaluated for the potential risk for insulin resistance, obesity, subclinical atherosclerosis, diabetes, metabolic syndrome and cardiovascular disease. Obesity is the most prominent predictor of metabolic syndrome. As the incidence of obesity is increasing both in childhood and adolescence, governments will be faced with a social and economic burden in the future. Adolescents with PCOS are more obese than normal adolescents and have an increased risk of metabolic syndrome. It is suggested that abdominal adiposity increases the risk of metabolic syndrome by inducing various cytokine secretions. Although there is no consensus on metabolic syndrome criteria in the adolescent period, International Diabetes Federation (IDF) criteria may be used for children older than 10 years. Various clinical and metabolic markers are investigated for the prediction of metabolic syndrome in the literature. Waist circumference, serum triglycerides and androgens are the suspected predictors of metabolic syndrome. The prevention of abdominal adiposity and the early diagnosis of PCOS in adolescence should be the main target for the prevention of metabolic syndrome. Clinicians should investigate adolescents with PCOS for metabolic and cardiovascular risks and take preventive action. A Mediterranean diet, low in fat and high in fruits and vegetables, along with moderate-intensity exercise and smoking cessation are the recommended interventions for especially obese adolescents with PCOS. Metformin may be the treatment of choice when lifestyle modifications are ineffective.