Objects To study the application of monitoring central veneus pressure in the blood purification and it's significance for ultrafiltration volume. Methods Twenty-two maintenance hemodialysis patients who received CVP monitoring from 1996 to 2003 in our dialysis center were selected as group A. Their ultrafiltration volume, blood pressure(BP) amd heart rate(HR) during dialysis and their Bp, heart function and body condition during the interm of dialysis were observed. Thirty-one dialysis patients who did not receive CVP monitortry and had same general condition were selected as group B. The incidence of hypotension during hemodialysis, heart failure during the intermission of hemodialysis and the score of APACHE III were compared between the two groups. The ultrafiltration volume during blood purification and the dehydration volume estimated clinical signs of group A were compared. Results There were significant difference between the two groups of the incidence of hypotention during hemodialyis, heart failune during the intermission of blood purification and score of APACHE III ( P<0.005). There were also significant difference of ultrafiltration volume during bolld purification and the delydration volume estimated by clinical signs of group A (P<0.005). Conclusions CVP monitoring is helpful for hemodialysis patients to observing the ambulatory changing of circulating blood volume. It has a guiding significance to adjust ultrafiltration volume on time and auurately and to improve heart function and prognosis for those severe patients.