The aim of this graduate thesis was to examine the relationship between stressful and traumatic life events and positive mental health of high school students in Varaždin County. In addition, the level of positive mental health, the frequency of experiencing stressful and traumatic events, and the gender differences between these constructs were examined. This research is part of a larger project called "Positive Adolescent Development in Croatia" which in the period from 2017 to 2019 examined 10,138 adolescents about the specifics of their development and the characteristics of family, peers, community and school environment. The research included a representative sample of 1 647 high school students from the area of Varaždin County. Participants were included from the following high schools: 143 students of the Medical School, 154 students of the School of Architecture, Science and Mining, 196 students of the School of Mechanical Engineering and Traffic, 234 students of the School of Economics, 204 students of the First Gymnasium, 178 students of the Second Gymnasium, 153 students of the Secondary Vocational School, 305 students of the School of Electrical Engineering and 80 students of the Music School. In addition to demographic data, positive mental health was examined by the Warwick-Edinburg Mental Wellbeing Scale (Stewart-Brown et al., 2007) and stressful and traumatic events by the Life Events Questionnaire specially designed for the project based on similar questionnaires. For the purposes of this thesis, the events were divided into everyday events and traumatic events. The results showed that adolescents from Varaždin achieve an average level of positive mental health (M=50,91; SD=10,44), with boys achieving a higher level than girls. Regarding the experienced stressful and traumatic events, the average result is five experienced events, with girls being shown to experience more stressful events. In addition, a negative correlation between positive mental health and stressful and traumatic events was confirmed.