Aim To evaluate application value and analyze risk factors of cardio-ankle vascular index (CAVI) in arterial stiffness in peritoneal dialysis patients. Methods A total of 95 patients with end-stage kidney disease undergoing peritoneal dialysis were enrolled, baseline characteristics and laboratory measurements were collected, and CAVI was determined. According to CAVI, the patients were divided into high CAVI group (CAVI≥9) and normal CAVI group (CAVI＜9). Results The CAVI was significantly higher in high CAVI group (9.85±0.73) than that in normal CAVI group (7.67±0.81). The age (54.64±5.68 years), dialysis duration (48.32±30.43 months), pulse pressure (57.41±12.43 mmHg), serum correctional calcium (2.52±0.28 mmol/L), phosphorus (2.22±0.66 mmol/L), calcium-phosphorus product (5.59±1.70), fasting blood glucose (6.02±1.83 mmol/L) were significantly higher in high CAVI group than those in normal CAVI group, hemoglobin (83.96±20.53 g/L) and serum albumin (32.40±5.22 g/L) were significantly lower in high CAVI group than those in normal CAVI group.Spearman correlation analysis showed that CAVI was positively correlated with age, dialysis duration, pulse pressure, serum correctional calcium, phosphorus, the calcium-phosphorus product, fasting blood glucose, hs-CRP(r values were 0.0,0.0,0.4,0.7,0.1,0.8,0.5,0.298 respectively, each P＜0.05), and negatively with serum albumin, 25-hydroxyvitamin D (r values were －0.335, －0.222, each P＜0.05). Multiple linear regression analysis showed that age and serum albumin were independent risk factors of CAVI. Conclusion CAVI can be used as an index of noninvasive detection of atherosclerosis in patients with peritoneal dialysis, early detection of CAVI and improving nutrition can reduce the risk of atherosclerosis in peritoneal dialysis patients, the incidence of cardiovascular events, and improve the prognosis.