Objective To analyze the risks for major adverse cardiovascular events (MACE) and stroke in elderly male patients with obstructive sleep apnea (OSA). Methods A multicenter clinical trail was carried out in several hospitals including Chinese PLA General Hospital and Peking University International Hospital during January 2015 to October 2017. A total of 675 consecutive elderly male OSA patients were eligible for inclusion and divided into mild OSA group (control group), moderate OSA group and severe OSA group according to sleep apnea hypopnea index (AHI). All of them were followed up regularly (every 3 months). The end events of follow-up were MACE and stroke. SPSS statistics 26.0 was used for data analysis. Kaplan-Meier survival analysis was employed to describe the cumulative incidence of terminal events, Log-rank test was adopted to compare the cumulative incidence between groups, and multivariate Cox regression analysis was performed to analyze the risks of MACE and stroke in the patients. Results There were statistically significant differences in age, body mass index (BMI), oxygen desaturation index(ODI), mean oxygen saturation (MSaO₂), minimum oxygen saturation, percentage of the times for SaO₂＜90% in total monitoring time during overnight sleep(TS90%) and occurrence of carotid atherosclerosis among three groups (P＜0.05). The cumulative incidence of stroke was the highest in severe OSA group, and the difference was statistically significant (P＜0.05). There was no significant difference in cumulative incidence of MACE among three groups(P＞0.05). Cox proportional hazard regression analysis showed that during the median follow-up period of 43 (41-55) months, only the patients with severe OSA were associated with an increased risk of stroke when compared with the control group (HR=5.43,95%CI 1.56-18.82, P<0.05); age (HR=1.04,95%CI 1.01-1.08, P<0.05) and history of carotid atherosclerosis (HR=2.64,95%CI 1.51-4.63, P<0.05) were independent risk factors for MACE in elderly male patients with OSA, but the severity of OSA was not related to the increased risk of MACE. Conclusion The elderly male patients with severe OSA are of high risk for stroke, but the severity is not related to the risk of MACE.