Background As a new a2-adrenoceptor agonist, dexmedetomidine plays key roles in sedation, analgesia as well as inhibition of sympathetic. Since it has advantages of fast effect and rapid clearance, and has no effect on the repiratory, it’s widely used in pediatrics at home and abroad. Objective To understand the application of dexmedetomidine in pediatrics and provide the reference for clinical use.Content This article summarizes the pharmacokinetics of dexmedetomidine in children and its impacts on respiration and circulation, and in particularly discusses its applications in common clinical fields in pediatric such as painless pediatric imaging services, pediatric anesthesia as well as pediatric Intensive Care Unit (PICU）. Trend Dexmedetomidine has unique advantages not only in the sedation for non-invasive examinations but also in the prevention and treatment of postoperative delirium.