Neurosteroids play a significant role in neurodevelopment and are involved in a wide variety of psychopathological processes. There is accumulating evidence on their role in adult psychopathology, including Alzheimer disease, schizophrenia, mood disorder, anxiety disorders and post-traumatic stress disorder. Little is known, however, about the possible role of neurosteroids in child and adolescent psychopathology although there is increasing evidence for their critical role from the early stages of brain development until adolescence. In this review we focus on the involvement of neurosteroids in neurodevelopment and mental disorders in children and adolescents. Adequate physiological levels protect the developing neural system from insult and contribute to the regulation of brain organization and function. Neurosteroids may be involved in the pathophysiology and pharmacotherapy of a variety of disorders in children and adolescents, including schizophrenia, depression, eating disorders, aggressive behavior and attention deficit. The complex interaction between neurosteroids, neurodevelopment, life-events, genetics and mental disorders in children and adolescents merits further investigation.