Objective To compare the efficacy and safety of remimazolam vs propofol for children undergoing painless gastroscopy. Methods A total of 129 children aged 4 ~ 9 years， ASAⅠ-Ⅱ， BMI 18 - 30 kg/m²， scheduled for painless gastroscopy under intravenous general anesthesia were divided into two groups by random number table method: remimazolam group （R group） and propofol group （P group）. Anesthesia was induced with sufentanil 0.2 μg/kg and penehyclidine hydrochloride 0.01 mg/kg. The patients in R group was given 0.5 mg/kg remimazolam and in P group was given 0.3 mg/kg propofol. The success rate of completing painless gastroscopy， heart rate， blood pressure， pulse oxygen saturation， sedation score， narcotrend index were recorded. The onset time, recovery time of orientation and adverse reactions were observed. Results The success rate of sedation in R group and P group was 82.8% and 90.8% respectively，with no statistically difference （P > 0.05）. At the time of endoscopic insertion and the end of endoscopic operation， the narcotrend index value of R group was 84.7 ± 10.8， 86.4 ± 4.3, respectively, which was significantly higher than that of P group （58.9 ± 13.2 and 66.2 ± 5.0） （P < 0.05）. The postoperative recovery time of R group was （14.2 ± 6.9） min， which was lower than that of P group （23.8 ± 6.7） min（P < 0.05）. The incidence of injection pain in R group and P group was respectively 10.9% and 52.3%， with statistically significant difference（P < 0.05）. And the other adverse reactions were not statistically significant （P > 0.05）. Conclusion Both remimazolam and propofol could be safely and effectively used gastroscopy for children, and remimazolam made patients wake up quickly with a lower incidence of injection pain.