A prospective study carried out in Bamako, Mali between July 1998 and January 1999 has assessed the seroprevalence of hepatitis C virus (HCV) in 91 carrier patients of chronic hepatopathy at a cirrhrosis stage (53) or of hepato-cellular carcinoma (38) and to compare with in 92 blood donors as a control population. Only seroprevalence confirmed by a complementary test has been taken into account (RIBA). HCV seroprevalence reached 25% including all hepatopathies, 24% in cirrhrosis and 26% in hepato-cellular carcinomae (HCC) versus 4% in blood donors. Antigen HBs of hepatitis B virus has been found in 55% of patients, versus 25% of the control cases (p = 0.0006). On the whole, the two markers have been notified a little more often in HCC than in cirrhosis and the combination of the two markers has been more frequent during cirrhosis as well. The role of HCV played in cirrhosis and HCC onset in Mali appears to be important.