Objective  To explore the relationship between high sensitivity C reactive protein to albumin ratio (CAR) and abdominal aortic calcification and all-cause death in patients with maintenance hemodialysis (MHD).  Methods  Patients with MHD who were treated in the Blood Purification Center of Beijing Luhe Hospital affiliated to Capital Medical University from January 2023 to February 2024 were selected. The basic information and laboratory data after 3 months of regular dialysis treatment were collected in the enrolled patients, as well as the data of abdominal aortic calcification and all-cause death. The correlation between CAR and abdominal aortic calcification was analyzed. The diagnostic value of CAR for calcification was analyzed by receiver operating characteristic curve (ROC), and the relationship between CAR and all-cause death was analyzed by logistic regression.  Results  A total of 204 patients were enrolled, including 155 patients (75.98%) with abdominal aortic calcification, and 11 patients (5.39%) with death. CAR in abdominal aorta calcification group was significantly higher than that in non-calcification group (Z=3.105, P=0.002), spearman correlation analysis showed that CAR was positively correlated with abdominal aorta calcification (r=0.218, P=0.002). The CAR cutoff value was 0.02mg/g for abdominal aorta calcification, the sensitivity and specificity were 92.9% and 36.7%, respectively, with an area under the curve of 0.647 (95% CI: 0.554～0.741, P=0.002). Logistic regression analysis showed that age, dialysis age and HbAlc were independent risk factors for abdominal aortic calcification (OR=1.074, 1.015, 1.881; 95% CI:1.040～1.110, 1.007～1.024, 1.188～2.978; P＜0.001, ＜0.001, =0.001) , and that CAR was an independent risk factor for all-cause death (OR=5.393, 95% CI:1.089～26.699, P=0.039).  Conclusion  CAR is positively correlated with abdominal aorta calcification, CAR is helpful for the diagnosis of abdominal aorta calcification, and CAR is an independent risk factor for all-cause death.