The results of the epidemiological, clinical and laboratory investigations, carried out in the 1994-1997 interval in the Iaşi district, on various populational groups, to indicate the prevalence of the antibodies anti-HVC possessors are presented. In 3611 patients with clinical-epidemiological HCV diagnosis, it was recorded a prevalence of the anti-HCV antibodies (AcHCV) presence of 22.7%. Posttransfusional hepatitis, epidemiologically diagnosed in 205 hospitalised patients was attributed to HCV in 11.6% of the cases, and in 94 patients with neurological diseases, AcHCV were identified in 9.6%. The presence of AcHCV at 825 persons in medico-sanitary staff, from risk domains, has recorded a prevalence of 8.0%. In the January 1997-September 1997 interval, the investigation by IIIrd generation ELISA of 51,149 blood samples of donors from various areas indicated the presence of AcHCV with an interval average of 2.6%.