The main aim of this study is to examine the prevalence of depressive symptoms among adolescents. The specific objectives are related to exploring the gender and age differences in occuring symptoms among adolescents from the examination group. The survey was conducted during April and May in three high schools in the city of Zagreb. The sample consisted of 220 students, 89 of them are students from the First Gymnasium, 90 are students from Graphic School for Media production and Design and 41 students from the Veterinary High School. The survey was conducted in the framework of the pilot project "The positive development of adolescents from City of Zagreb: state of the art" on the Faculty of Education and Rehabilitation Sciences, University of Zagreb. For the purposes of this project, an instrument was developed that consists of several different scales, in order to answer to the research questions, out of whole instrument, these were taken into account: (1) questionnaire on demographic data and (2) Depression Anxiety Stress Scale-21. Participation in the survey was voluntarily and anonymous. The survey was conducted with group of students during the class and the paper-pencil method was used in the research. The results have shown that among adolescents there are the most of those who do not have any depressive symptom, on the other hand there are 12,3% of students that are showing depressive symptomatology in a great mesaure. There are no gender differences found among prevalence of depressive symptoms. Moreover, there are no age differences in prevalence of depressive symptomatology. Results have shown that the depressive symptoms are at the peak entering the adolescence and that with increase of age there is a decrease of symptoms among adolescents.