Background：Pain is one of the most serious clinical problems beset mankind. In clinic, dexmedetomidine are widely used for preoperative, intraoperative and postoperative sedation and analgesia. Objective: To make clear whether application of dexmedetomidine to perioperative analgesic has many advantages? Content: Clinical studies have shown that dexmedetomidine is beneficial when used for preemptive analgesia and auxiliary analgesia, and is helpful to maintain stability of hemodynamics, prolong the analgesia duration of anesthetics, and reduce adverse reactions of perioperative analgesia, especially in some special patients, such as obstetric anesthesia and pediatric anesthesia. Trend: The best time and way of dexmedetomidine in perioperative analgesia and the choice of patients still needs more research to confirm.