OBJECTIVE Adolescent headaches, particularly migraine, might present with different features from adult headaches. The objectives of this study were to investigate the characteristics of tension-type headache and migraine, to find the sensitivity and specificity of the diagnostic criteria of the IHS classification according to age and gender. METHODS A multistep, stratified, cluster sampling method was used for subject selection. The estimated sample size was 2387. The study was conducted in two phases: the questionnaire and the face to face interview phases. During the semistructured interview, a clinical diagnosis has been made and clinical characteristics have been recorded. RESULTS All headaches fulfilled the criteria of duration. The most common feature of migraine was moderate to severe (92.4%), pulsating pain (79.2%). For ETTH, bilateral localization (91.3%) and mild to moderate pain intensity (90.6%) were the most common features. Younger adolescents showed mixed headache characteristics. Highest sensitivities for migraine were duration (100%), moderate to severe pain (92.4%), and pulsating quality of pain (79.2%). Vomiting, trigger factors food and alcohol had a high specificity for migraine. CONCLUSIONS Our data strongly support continuum hypothesis. In early adolescence headaches might present with mixed headache characteristics. Age and gender have some influence on headache characteristics, particularly on migraine. The sensitivity and specificity of case definition criteria of ICHD-2 for adolescent migraine is moderate and need to be reconsidered.