Background/Aims: The basic principle of treatment of congestive heart failure is achieving adequate control of preload and afterload through enhancement of cardiac contractility. In severe cases, however, we have usually applied continuous hemodiafiltration (CHDF) as a type of mechanical support. In this study, we investigated hemodynamic changes caused by CHDF in patients with congestive heart failure. Methods: We treated seven patients with congestive heart failure complicated by multiple organ failure by CHDF over 72 h, during which we measured hemodynamic parameters to determine their changes. Results: Implementation of CHDF resulted in a significant decrease in pulmonary artery occluded pressure and significant increases in cardiac index and left ventricular stroke work index. In addition, 72-hour cumulative water balance was found to be –1,791 ± 2,119 ml, and systemic vascular resistance index decreased significantly. Conclusion: Hemodynamics of patients were improved with CHDF through strict control of preload and consequently tissue oxygen metabolism was improved.