We proposed to evaluate the association between serum indirect bilirubin levels and liver fibrosis in patients with chronic hepatitis C (CHC) genotype 1b. Biopsy proven CHC genotype 1b patients' demographics, clinical and histopathological characteristics were evaluated. Logistic regression analysis was done to evaluate the clinical, laboratory and demographic features of the histologically proven liver fibrosis in CHC patients. A total of 112 biopsy proven CHC genotype 1b patients were enrolled into the study. Liver fibrosis scores were measured by using Ishak fibrosis scores and were divided into two groups; fibrosis scores <= 2 were categorized as mild fibrosis, 82 patients (73.2%), whereas fibrosis scores >2 were categorized as advanced fibrosis group, 30 patiens (26.8%). Patients with advanced fibrosis had lower indirect bilirubin levels than the mild fibrosis group (0.28 +/- 0.02 mg/dl vs. 0.44 +/- 0.032 mg/dl, p < 0.001, respectively). Indirect bilirubin level was negatively correlated with advanced fibrosis scores (r = -0.416 and p < 0.001). In multivariate logistic regression analysis, low indirect bilirubin level was an independent predicting factor of advanced liver fibrosis (OR: 0.001, 95% CI: 0.0-0.005, p < 0.001). There is an inverse relationship between indirect bilirubin levels and advanced liver fibrosis caused by CHC genotype 1b. (C) 2014 Elsevier GmbH. All rights reserved.