The period of childhood and adolescence is characterized by an increased vulnerability to the onset of mental disorders, which predisposes individuals to the development of mental disabilities and impacts both the duration and quality of life. Psychopharmacological treatment is a crucial component of the multimodal intervention approach for addressing mental health conditions in children and adolescents. However, prescribing decisions and drug choices often entail intricate considerations, particularly within the realm of child and adolescent psychiatry where empirical evidence remains limited. The objective of this chapter is to furnish scholars, medical practitioners, psychologists, physicians, and medical students with a comprehensive medication reference for child and adolescent psychiatric care, focusing on the commonly prescribed first-line medications. First, the severity and classification of mental disorders in children and adolescents are discussed. Subsequently, the mechanism and classification of corresponding drugs based on common primary mental disorders in this population are presented and introduced. Additionally, the pharmacodynamics, pharmacokinetics, adverse effects, and precautions associated with the most frequently utilized medications are described. Finally, a brief comparison is made between recommended medications in the US and China.