INTRODUCTION. In patients with chronic hepatitis C it is still debated whether previous exposure to the hepatitis B virus, diagnosed from the presence of the anti-HBc antibody, is linked to a greater risk of severe hepatitis. The aim of the study was to evaluate whether the presence of anti-HBc antibodies is associated with cirrhosis in patients with HBsAg-negative chronic hepatitis C. MATERIAL AND METHODS. Two hundred twenty-two consecutive HBsAg-negative patients with HCV-related chronic hepatitis were enrolled at their first liver biopsy. Ishak's scoring system was used to grade necroinflammation and fibrosis and the patients with stage 5 or 6 were considered as having histological cirrhosis. RESULTS. Patients with histological cirrhosis had a higher mean age, AST, ALT, a lower platelet count and prothrombin activity compared to those with milder fibrosis. The presence of anti-HBc was identified in 21 (63.6%) of the 33 patients with fibrosis score 5 or 6 and in 56 (29.6%; p < 0.001) of the 189 with score ≤ 4. Patients with cirrhosis had a significantly higher grading than those without cirrhosis (median = 8, IQR 6-11 vs. Median = 6, IQR = 4-8, respectively, p < 0.001). A multivariate logistic regression analysis showed that age, sex and anti-HBc positivity were independent predictors of histological cirrhosis. CONCLUSION. Our data support the idea that in patients with chronic hepatitis C the presence in serum of anti-HBc is associated with histological cirrhosis and is therefore a marker of clinical value.