ABSTRACTIntroduction:Mental health of adolescents can affect growth and development, decrease school performance, and impair social relationships with peers and families. The COVID-19 pandemic has changed the social and educational scenario and affected the psychological condition of children and adolescents. This study aimed to find out the prevalence of depression, anxiety and stress among school-going adolescents in a secondary school.Methods:A descriptive cross-sectional study was done among school-going adolescents of a school from 1 October 2021 to 31 November 2021. Ethical approval was taken from the Institutional Review Committee (Reference number: 0609202101). Data was collected using a questionnaire consisting of sociodemographic parameters and a diagnosis of depression anxiety and stress was made using a standard scale. The whole sampling method was used. Percentage and frequency were calculated for binary data.Results:Among 95 patients, the depression was found in 31 (32.63%), anxiety in 36 (37.89%), and stress in 3 (3.16%).Conclusions:The prevalence of depression, anxiety and stress was lower than in other studies done in similar settings. The mental health status of school-going adolescents should be identified and appropriate timely interventions need to be taken. Family members, teachers and the concerned authorities should give emphasis to the psychological well-being of the adolescents.