Objective:To evaluate the efficacy of SedLine Brain Function Monitor-guided total intravenous anesthesia for children undergoing hypospadias surgery.Methods:This was a randomized controlled trial. A total of 161 children, aged 1-10 yr, with American Society of Anesthesiologists Physical Status classification ⅠorⅡ, scheduled for elective hypospadias surgery, were divided into SedLine group (S group, n=83) and control group (C group, n=78) using a random number table method. In group S, 95% spectral edge frequency (SEF 95) was maintained at 14-18 Hz, and the patient state index (PSI) was maintained at 25-50 during surgery. In group C, mean arterial pressure was maintained at 60-80 mmHg, and heart rate was maintained at 80-110 beats/min during surgery. PSI and SEF 95 were recorded before induction (T 1), at 0, 5 and 10 min after intubation (T 2-4), at the beginning of surgery (T 5), at 30 min and 1 h after surgery (T 6, 7), and at the end of surgery (T 8). The anesthetic duration, operation time, time from withdrawal to extubation, postanesthesia care unit duration, consumption of propofol and remifentanil, intraoperative adverse events, 5-point Likert scale scores, and emergence delirium scores were recorded. Results:Compared to C group, the total anesthesia time, time from withdrawal to extubation and postanesthesia care unit duration were significantly shortened, the consumption of propofol for both induction and maintenance was reduced, the PSI at T 5-8, SEFL 95 at T 2-6, and SEFR 95 at T 2-8 were increased, and the incidence of intraoperative body movement and incidence of emergence agitation were decreased in S group ( P<0.05). Conclusions:SedLine Brain Function Monitor-guided total intravenous anesthesia provides better efficacy when used for the children undergoing hypospadias surgery.