The depressive disorder in children and adolescents has severe disease burden and is characterized by low rates of early identification and consultation， as well as a high rate of misdiagnosis. There are difficulties in the clinical diagnosis and treatment process， such as the complicated etiology and the unclear pathogenesis， lack of objective diagnostic markers and lack of safe and effective treatment methods. This article reviews the research on the diagnosis and treatment of depression in children and adolescents， focusing on the aforementioned issues.