Objective To investigate the effect of remimazolam combined with butorphanol in outpatient painless gastroenteroscopy. Methods According to the random number table method, 70 patients who were scheduled for painless gastroenteroscopy were divided into two groups (n=35): propofol group (group A) and remimazolam group (group B). Anesthesia induction program: group A was given butorphanol tartrate 0.6 mg combined with propofol 1.5‒2.0 mg/kg, group B received butorphanol tartrate 0.6 mg combined with remimazolam 0.2 mg/kg. Both groups were compared for the incidence of perioperative hypotension and hypoxemia. Their mean arterial pressure (MAP), heart rate, pulse oxygen saturation (SpO2) and bispectral index (BIS) before surgery (t1), at the beginning of surgery (t2), 5 min after surgery (t3), 10 min after surgery (t4), at the end of surgery (t5), and after fully emergence (t6) were recorded. The anesthetic effect, emergence time, dosage times of rescue analgesia, and adverse reactions were observed. The patients were followed up 4 h and 24 h after leaving endoscopy center. Results Compared with group A, group B presented remarkably reduced incidence of hypoxemia (P<0.05). There was no statistical difference in the incidence of hypotension between the two groups (P>0.05). The MAP of group A was lower than that of group B at t2, t3, t4 and t5 (P<0.05). The heart rate of group A was lower than that of group B at t4 (P<0.05). The BIS value in group A was lower than that in group B at t2 and t4 (P<0.05). There were no statistical differences in SpO2 between the two groups at each time points (P>0.05). There was no significant difference between the two groups in the rate of anesthetic effect, emergence time and the dosage number of rescue analgesia (P>0.05). The percentage of injection pain obviouisly decreased in group B, compared with group A. The difference in adverse reactions between the two groups was statistically significant (P<0.05). There was no significant difference in the incidence of dizziness after recovery between the two groups (P>0.05). Conclusions In combination with butorphanol tartrate, remimazolam is used in painless gastroenteroscopy and achieve an anesthetic effect not inferior to that of propofol, with less respiratory and circulatory system inhibition and a low incidence of adverse react ions, which is an effective scheme for outpatient intravenous anesthesia.