Background Ketamine is an anesthetic which has been widely used for anesthesia and analgesia in the clinic for many years. In recent years, it is found that a low-dose of ketamine can exert a robust, rapid and relatively sustained antidepressant effects. Objective To understand the physical and chemical properties of the antidepressant effects of ketamine, and to recognize the unique advantages of the ketamine. Content To survey the basic and clinical research of the antidepressant effects of ketamine by reviewing domestic and international literatures，and to summarize the results of the reseach. Trend With the understanding of current research of ketamine in depression, ketamine is a promising antidepressant in future which deserves further research.