Objective The purpose of this study was to determine the median and 95 percent effective doses （ED50，ED95）of propofol and remifentanil for endotracheal intubation without muscle relaxant in pediatric patients using a sequential method. Methods In two stages，70 children undergoing elective surgery were chosen for the sequential trial. In the first stage，the induction dose of propofol was fixed at 3.5 mg/kg，and the ED50 and ED95 of remifentanil were measured. In the second stage，the ED95 of remifentanil was fixed，and the ED50 and ED95 of pro⁃ pofol were measured. Using the probit probability unit process，the ED and 95 percent confidence interval（CI） were measured. Results The ED50 of remifentanil was 2.50（95%CI 1.91，3.28）μg/kg，and the ED95 was 3.91 （3.19，9.53）μg/kg. The ED50 of propofol was 2.34（1.73，2.94）mg/kg，and the ED95 was 3.67（3.02，8.65）mg/kg. Conclusions Propofol and remifentanil can be used safely in children aged 1 to 3 years old for endotracheal intu⁃ bation without the use of a muscle relaxant.Propofol and remifentanil have ED50 and ED95 values that can be used as a guide for specific drug administration。