Objective ：Discuss the appilication of depth of anesthesia index during total intravenous anesthesia, and compare with Narcotrend index . Methods ：Choosing 30 cases of patients who were for Laryngeal surgery, aged 18-65, ASA I to II. All patients were monitored by AI，NI and propofol effect-site concentrations. After anesthetic induction and endotracheal intubation, Propofol and remifentanil were continuously infused to maintain adequate depth of anesthesia. Recorded AI, NI, and Ce at different time point. Results ：The correlation coefficients of AI, NI and Ce are 0.913，-0.599, the correlation coefficients of NI and Ce are -0.584, there is a good correlation between AI、NI and Ce. Conclusions： Both of AI and NI can reflect the depth of anesthesia under different stimulation. During total intravenous anesthesia, AI can better control the depth of anesthesia, help guide rational drug use and avoid intraoperative awareness.