PURPOSE: Knowledge about polyphenols intakes and their determinants among adolescents might be helpful for planning targeted prevention strategies at an early age. METHODS: In the European multicenter cross-sectional HELENA study of 2006-2007, 2428 subjects (47% boys) had data on dietary intake of polyphenols from 2 non-consecutive 24 h recalls via linking with the Phenol-Explorer database. Differences by sex, age, country, BMI, maternal education, paternal education, family affluence, smoking status, alcohol use, and physical activity were explored by linear regression. RESULTS: Median, lower and upper quartiles of polyphenol intakes were 326, 167 and 564 mg/day, respectively. Polyphenol intake was significantly higher in the oldest (16-17.49 years), girls, non-Mediterranean countries, lowest BMI, highest paternal education, and alcohol consumers. Main food contributors were fruit (23%, mainly apple and pear, i.e., 16.3%); chocolate products (19.2%); and fruit and vegetable juices (15.6%). Main polyphenol classes were flavonoids (75-76% of total) and phenolic acids (17-19% of total). The three most consumed polyphenols were proanthocyanidin polymers (> 10 mers), hesperidin, and proanthocyanidin 4-6 oligomers. CONCLUSION: The current study provided for the first time numbers on the total polyphenol intake and their main food sources in a heterogeneous group of European adolescents. Major differences with adult populations are the lower polyphenol consumption and the major food sources, such as chocolate and biscuits. The discussed determinants and polyphenol types already point to some important population groups that need to be targeted in future public health initiatives.