We measured urokinase-type plasminogen activator (u-PA) plasma levels in patients with various chronic liver diseases, including hepatocellular carcinoma (HCC), also measuring these levels in healthy volunteers. Plasma u-PA levels in the group of patients with decompensated liver cirrhosis (mean modified Pugh score of 14 points) were markedly elevated and significantly higher than those in the patients with decompensated liver cirrhosis with HCC (modified Pugh score of 10 points), those with compensated liver cirrhosis with HCC, and those with compensated liver cirrhosis. Patients in all these three latter groups had moderately and significantly elevated u-PA levels compared to levels in the chronic hepatitis group and the healthy volunteers, but the levels were not significantly different from each other. There was no relationship between u-PA plasma level and the type of HCC tumor invasion or number or size of tumors. Significant correlations were found between u-PA plasma levels and the results of seven different liver function tests in three groups without associated HCC; u-PA antigen and prothrombin time (%), hepaplastin test (%), serum cholinesterase, serum albumin, serum total cholesterol, and indocyanine green clearance correlated negatively, while u-PA antigen and serum total bilirubin correlated positively. These results suggest that plasma u-PA is associated with deterioration of liver function but not with HCC invasion.