Purpose: Evaluating the nutritional status of patients with Maintenance Hemodialysis (MHD) based on CONUT score to explore its relationship with Cardiovascular Disease (CVD) in MHD patients. Methods: Baseline data of new-coming MHD patients hospital hemodialysis center of our hospital undergoing hemodialysis treatment for the first time from January 1, 2014 to June 30, 2020 was collected. Cardiovascular events were used as the end point. Patients were divided into three groups according to CONUT score: normal nutrition group (CONUT score 0-1), mild malnutrition group (CONUT score 2-4) and moderate to severe malnutrition group (CONUT score ≥5), and the differences of clinical data and prognosis among the three groups were compared. The risk factors of cardiovascular events in MHD patients were determined by Logistic regression analysis, and the predictive ability of the risk factors was observed with Receiver Operating Characteristic (ROC) curve. Results: A total of 424 MHD patients were included. According to the CONUT score, 31 (7.3%) patients were in the normal nutrition group, 160 (37.7%) patients in the mild malnutrition group, and 233 (55.0%) patients in the moderate to severe malnutrition group. A total of 159 patients had cardiovascular events, including 3 cases (9.7%) in the normal nutrition group, 38 cases (23.8%) in the mild malnutrition group, and 118 cases (50.6%) in the moderate to severe malnutrition group. The worse the nutritional status of patients is, the higher the incidence rate of cardiovascular events is (P<0.05). Logistic regression analysis showed that CONUT score and age were independently correlated with cardiovascular events in MHD patients (P<0.05). ROC curve analysis showed that CONUT score and age predicted cardiovascular events in MHD patients with areas under the curve were 0.683 (95% CI: 0.632-0.735, P<0.001) and 0.702 (95% CI: 0.702), respectively. 0.652 -- 0.753, P<0.001), the optimal cut-off points were 4.5 (≥5 in combination) and 68.5, the sensitivity were 74.2% and 49.1%, and the specificity was 56.6% and 81.1%, respectively. Conclusion: There is a certain correlation between CONUT score the happening of cardiovascular events and MHD patients.