Objective: To investigate the anesthetic effect of remimazolam tosylate in painless gastroenteroscopy in elderly patients, and to explore the effect on postoperative cognitive function. Methods: A total of 96 elderly patients who planned to undergo painless gastroenteroscopy in the outpatient department of Wuxi 9th People’s Hospital Affiliated to Soochow University from September 2019 to June 2021 were randomly divided into a control group and a study group. Patients in the control group were given intravenous anesthesia scheme of propofol + sufentanil, and patients in the study group were given intravenous anesthesia scheme of remimazolam tosylate + sufentanil, which was operated by endoscopists in the same group. The heart rate (HR), mean arterial pressure (MAP) and blood oxygen saturation (SpO₂) of the 2 groups before anesthesia (T0), 3 minutes of anesthesia (T1), 10 minutes of anesthesia (T2) and awakening (T3) were monitored, the anesthesia related indexes of the 2 groups were compared, and the cognitive function of the two groups was evaluated by Mini-Mental State Examination (MMSE). Results: Compared with T0 time point of this group, HR, MAP, and SpO₂ decreased significantly at T1–T2 time points of the 2 groups (all P<0.05). HR, MAP, and SpO₂ in the study group at T1 time point were higher than those in the control group (all P<0.05), and HR and SpO₂ at T2 time point were higher than those in the control group (both P<0.05). There was no significant difference in the effective time of anesthesia between the 2 groups (P>0.05). The recovery time, hospital leaving time and adverse reaction rate of anesthesia in the study group were shorter or lower than those in the control group (all P<0.05). The MMSE score of the control group at 10 and 30 minutes after awakening was significantly lower than that before operation (P<0.05), and that of the study group at 10 minutes after awakening was lower than that before operation (P<0.05). The MMSE scores of the study group were higher than those of the control group at 10 and 30 minutes after awakening (both P<0.05). Conclusion: Remimazolam toluenesulfonate for painless gastroenteroscopy in elderly patients not only has better anesthetic effect, less adverse reactions, but also has less impact on cognitive function. It is worthy of popularization and application in outpatient clinic.