Background: the prevalence of self-harming behavior in modern society is high and is especially relevant for adolescents and young adults. Self-harm is considered as a risk factor for suicide. At the same time, the concept of self-harm remains insufficiently developed, and its relationship with suicidality remains unexplored. Domestic publications on the issue of self-harm are mainly devoted to the psychological aspects of the problem. The aim of review was to analyze existing ideas about self-harming behavior in scientific publications. Material and Method: the publications were searched in the electronic databases MEDLINE, Google Scholar, PubMed for the keywords “self-harm”, “non-suicidal self-harm”, “suicide”; “self-harm”, “non-suicidal self-injury”, “suicide”, “adolescence and youth”. The selection of publications was carried out manually. A descriptive approach was used to summarize the data. Conclusion: the review provides current data on the study of prevalence of self-harm among adolescents and youth, reveals the concept of self-harming behavior and its place in modern classifications of mental disorders, discusses contradictions in the use of the term. The researchs of self-harming and suicidal behavior risk factors are analyzed, including interrelations with mental disorders. A consensus of researchers has been established that non-suicidal self-harm is an important indicator in assessing the risk of depression and suicidality in young peoples. The research directions of assistance and prevention of self-harming and suicidal behavior in adolescence and youth are considered.