To explore the changes in blood levels of lipopolysaccharide(LPS), lipopolysaccharide-binding protein(LBP),and soluble CD14 (sCD14), and their clinical significance in patients with severe chronic viral hepatitis B. blood levels of LPS were determined with chromogenic limulus amebocyte lysate assay, and LBP and sCD14 were assayed with ELISA in 24 patients of severe chronic viral hepatitis B. 10 normal subjects and 16 patients with chronic hepatitis B were also enrolled as controls. The results showed that the blood levels of LPS, LBP and sCD14 were significantly higher in patients with the early stage, midterm, late periods of severe chronic viral hepatitis B than in normal subjects and in those with chronic hepatitis B. The blood levels of LPS, LBP and sCD14 were also significantly higher in patients who died of severe chronic viral hepatitis B than in survivors of the same disease. It suggested that when patients with severe chronic viral hepatitis B were complicated by intestinal endotoxemia (IETM), the sensitivity of Kupffer cells to endotoxin was significantly increased, resulting in hepatocyte injury by TNF ?,even in the presence of very low endotoxin concentration .