The aim of this study was to investigate the impacts of continuous veno-venous hemofiltration (CVVH) on plasma cytokines and monocyte human leukocyte antigen-DR (HLA-DR) expression and to evaluate the relationship between them during CVVH treatment in septic patients. Forty septic patients were enrolled in this study. They were randomly divided into control group (who received conventional treatment, n=20) and CVVH group (who received conventional treatment and CVVH treatment, n=20). The blood samples were taken to measure the changes of plasma cytokines (IFN-gamma, TNF-alpha, IL-1, IL-2, IL-4, IL-6, IL-10 and IL-13) and HLA-DR expression on monocytes. After CVVH treatment, the plasma levels of IFN-gamma, IL-1, IL-2, IL-4, IL-10 and IL-13 in septic patients were markedly decreased (P0.05). HLA-DR expression on monocytes improved in CVVH treated patients (P<0.05). No matter pre-treatment or post-treatment of CVVH, there was a negative correlation between plasma IL-10 and monocyte HLA-DR expression (P<0.05). In contrast, no obvious change was shown in control patients. Our findings suggest that CVVH is effective in removal of many plasma cytokines and in improvement of monocyte HLA-DR expression in septic patients.