The aim of this study was to compare the effectiveness of propofol-based sedation and midazo-lam sedation in same-day bidirectional endoscopy (BDE) in children. The charts of children (≤15 years old) who had undergone same-day BDE were retrospectively reviewed. Demographic data, indications, sedatives and their dosages, clinical outcomes, endoscopic findings, adverse events, and patient time requirements were compared in cases with propofol-based and midazolam se-dation. A total of 91 children [51 boys, mean age 13 years (range 9-15)] were enrolled. Propofol alone or in combination with midazolam and/or pentazocine was given in 51 (propofol-based sedation group) while midazolam alone or in combination with pentazocine was given in 40 (midazolam sedation group). The mean doses of propofol, midazolam and pentazocine were 96 mg (range 40–145 mg), 4.1 mg (range 3–5 mg) and 7.5 mg in the propofol group while the mean doses of midazolam and pentazocine were 6.2 mg (range 4–10 mg) and 15 mg in the midazolam group, respectively. The total procedure times and endoscopic findings between the two groups were similar, but the median patient time requirement in the propofol group was significantly shorter than that of the midazolam group (7.3 h vs. 8.4 h, P<0.001). No adverse events occurred in either group. Propofol-based sedation shortened patient time requirements in same-day BDE compared with midazolam sedation in children.