Abstract: Objective To investigate the relationship between continuous volume overload and large arterial stiffness in patients receiving continuous ambulatory peritoned dialysis（CAPD）.Methods All clinically stable CAPD patients（n=220） at our centre were followed up monthly using multi-frequency bioelectrical impedance analysis to assess volume status and carotid-femoral pulse wave velocity（PWV） as an index of large arterial stiffness for 6 months.Results All patients completed the study Male/Female（86∶134）,94 were classified as normal volume（NV）,79 intermittent volume overload（IVO） and 47 sustained volume overload（SVO）.At baseline the systolic blood pressure（SBP） was significantly higher in sustained volume overload SVO（144.8±20.9） vs IVO（135.5±23.4） vs NV（127.0±23.9） mmHg,P＜0.05 or P＜0.01;after 6 months this difference remained significant SVO（145.4±22.0） vs IVO（136.8±24.5） vs NV（130.0±26.0）mmHg,P＜0.05 or P＜0.01.PWV in both the SVO and IVO were significant higher than that in NV（12.6±1.6）,（12.2±2.3） vs（10.7±2.1） m/s,respectively,both P＜0.01.The serum albumin in the SVO and IVO were both significantly lower than the NV patients （36.9±4.0） vs（38.6±4.0） and（39.6±6.5） g/L,respectively,both P＜0.05.No significant changes were observed in PWV for the NV or IVO patients,however in the SVO patients PWV was increased associated with lower albumin,elevated SBP and hsCRP.Conclusion Our date study demonstrates that continuous volume overload is strongly associated with increased large arterial stiffness in CAPD patients,which might be related to blood pressure,or nutritional status.