Objective: To evaluate the effects of cardiopulmonary fitness on arteriosclerotic cardiovascular disease (ASCVD) events in patients with different risks of ASCVD. Methods: This study enrolled 544 non ASCVD patients who underwent cardiopulmonary exercise testing in Peking University Third Hospital from September 2016 to April 2018. ASCVD overall risk assessment was conducted according to “Chinese Guidelines for the Prevention and Treatment of Adult Dyslipidemia”. Peak oxygen uptake (VO₂peak), the classic indicator of cardiopulmonary fitness, was accurately determined by cardiopulmonary exercise testing in all the patients. All of the patients were followed up clinically. Results: In the study, 506 patients completed the follow-up (250 low-risk patients, 93 moderate-risk patients and 163 high-risk patients). The median follow-up period was 19 months (9-28 months), and 51 patients developed ASCVD events during the follow-up period, of whom, 33 cases developed myocardial infarction, unstable angina or coronary revascularization, and 18 cases ischemic stroke, transient ischemic attack or carotid vascular revascularization. The patients were divided into the ASCVD group (n=51) and the non ASCVD group (n=455) based on the presence or absence of ASCVD events. VO₂peak [16.3(3.6) mL(kg·min) vs. 19.1(3.2) mL/(kg·min), P<0.001] in the ASCVD group were significantly lower than that in the non ASCVD group. Logistic regression analysis found VO2peak [OR 0.893 (95%CI:0.831-0.959), P=0.002] and ASCVD risk stratification [OR 1.428 (95%CI:1.028-1.878), P=0.031] were both independently associated with the occurrence of ASCVD events, which meant that every 1 mL/(kg·min) of increase in VO₂peak, the risk of ASCVD events was reduced by 11%. The patients were divided into low, moderate, and high VO₂peak according to the tertiles of their VO₂peak [14.4 mL/(kg·min), and 23.0 mL/(kg·min)]. Logistic regression analyses were performed using ASCVD events as a dependent variable in the patients with high-risk and low/moderate-risk of ASCVD respectively. In the patients with high-risk of ASCVD, the results suggested that the incidence of ASCVD events was significantly decreased in the patients with moderate VO₂ peak [OR 0.210 (95%CI:0.054-0.814), P=0.024] and high VO₂ peak [OR 0.146 (95%CI:0.025-0.870), P=0.035], but no significant effect of VO₂ peak elevation on the incidence of ASCVD events was found in the low/moderate-risk ASCVD patients. Conclusion: High cardiopulmonary fitness can significantly reduce the occurrence of ASCVD events in patients with high-risk of ASCVD.