Serum levels of human hepatocyte growth factor (hHGF) in patients with various liver diseases were determined using an ELISA kit to explore its clinical significance. Significantly high levels of serum hHGF were found in patients with acute hepatitis, fulminant hepatitis, liver cirrhosis, and hepatocellular carcinoma. Increased levels of hHGF were observed during severe liver injury in patients who died of fulminant hepatitis. However, the levels returned to normal during the repair process of liver injury in the surviving cases. In patients with liver cirrhosis, serum hHGF levels were negatively correlated with serum albumin (Alb) levels. These results indicate that serum hHGF levels are not useful for detecting repair processes of the injured liver, but serve as an index of the severity of liver dysfunction in various liver diseases.