Symptoms of mental health among young people have increased significantly. New forms of support for adolescents’ mental health services are needed. Digital interventions improve access to mental health services and could be used in prevention in the future. The purpose of this thesis was to describe what kind of effects the digital interventions aimed at young people had in promoting their mental health. The aim of the thesis was to provide information about the impact of digital interventions in promoting adolescent mental health for young people, their parents, and professionals. The thesis was carried out as a descriptive literature review. The data was searched in three different databases using a research question and inclusion and exclusion criteria. Nine international peer-reviewed randomised controlled trials were included. The data was analyzed by the process of inductive content analysis. A reduction in stress symptoms compared to the control group was found in four studies, but no difference was found in two studies. The reduction in anxiety was found in two studies, but no difference was found in five studies. The intentions of seeking help were noted in two studies. In addition, improvement in mental well-being was reported in some studies. However, no significant results were found in three studies. Also in other studies, some of the results were left insignificant.