Abstract: The aim of this study was first, to evaluate the effects of continuous hemodiafiltration (CHDF) alone or combined with CHDF and polymyxin-B immobilized fiber (PMX) on survival rates of patients with sepsis and acute renal failure, and second, to evaluate the changes in plasma levels of inflammatory cytokines before and after treatment with CHDF and PMX and CHDF alone in these patients. Forty-eight patients with septic shock and acute renal failure were enrolled in this study. The survival rate of all patients at 28 days was 25% for those with CHDF and 75% for those with PMX and CHDF treatment. Combination treatment produced a significant reduction of plasma levels of endotoxin and interleukin-6 compared to the basal values and to the treatment with CHDF alone. From these data, it is suggested that the combined therapy with PMX and CHDF is effective in improvement of survival rate of patients with septic shock and acute renal failure.