Objective To compare the effect of oxycodone and sufentanil combined with etomidate for painless cystoscopy in the elderly male patients. Methods A total of 60 elderly male patients, aged 66 to 78 years, body mass 52-74 kg, American Society of Anesthesiology (ASA) Ⅱ-Ⅲ, were included in the study, who underwent cystoscopy in the Baoding Municipal First Central Hospital from October 2017 to May 2018. The patients were divided into oxycodone group and sufentanyl group with 30 each. The patients were intravenously injected with oxycodone (0.05 mg/kg) in oxycodone group, sufentanyl (0.05 μg/kg) in sufentanyl group, and 3 min later, etomidate (0.2 mg/kg) in both groups. Additional etomidate (0.1 mg/kg) was intravenously administered on frowning or body movement. Indices observed and recorded throughout the procedure included occurrences of frowning, body movement, respiratory depression, duration of cystoscopy, etomidate dosage, wake-up time, dizziness, nausea and vomiting. SPSS statistics 17.0 was used for data processing, and Student′s t-test and Chi-square test were performed for comparison. Results Compared with sufentanyl group, the incidence of frowning or body movement [10%(3/30) vs 47%(14/30)] and the dosage of etomidate [(13.2±2.1) vs (20.7±3.6)mg] decreased in oxycodone group (P<0.05). There was no statistically significant difference between the two groups (P>0.05) in the incidence of nausea and vomiting [3%(1/30) vs 20%(6/30)], respiratory depression [0%(0/30) vs 13%(4/30)] and dizziness [10%(3/30) vs 13%(4/30)]. Conclusion Oxycodone combined with etomidate is more effective than sufentanil for elderly patients undergoing cystoscopy.