Stressors play a defining role in youth development and, in particular, in adolescent psychological and behavioral adaptation. However, the nature of stressors experienced during adolescence has not been reviewed or investigated comprehensively. To bridge this gap, this investigation conducted a systematic review of adolescent stressors reported in the literature (Study 1, N = 18 studies) and a content analysis of self-reported stressors (Study 2, N = 1,568 adolescents, Mean age = 15.5 years, 41.5% female adolescents). The results converged in the identification of negative stressors (i.e., health issues, parental conflicts, issues with parents, teachers, peers or friends, romantic issues, concerns about the future and school) and positive stressors (i.e., leisure time, finding oneself, school or other accomplishments, social acquisitions, receiving help, romance and friendship, birth and good time in the family), which are highly occurring and highly intense among adolescents. Overall, these findings can guide researchers and practitioners towards developing efficient stressors measures, integrative theories on adolescent stress and development, as well as effective interventions targeting specific stress processes in the domains of education, criminology and psychopathology.