Abstract Background The aim of this study was to investigate the impact of anti-HBc (HBcAb) positivity on the progression of liver fibrosis (Fibrosis-4 score >3.25) in the Italian cohort of HIV-infected individuals naïve to antiretroviral treatment (ICONA). Methods All patients with FIB-4 <3.25 at baseline were evaluated prospectively: 6966 people with HIV (PWH) were screened and classified based on hepatitis B virus (HBV) and hepatitis C virus (HCV) serology. Results Patients who were HBcAb+/HCV-/HBs antigen (HBsAg)- and HCV+/HBcAb+/HBsAg- or HBsAg+/HBcAb+/HCV- had CD4+ cell counts below the nadir and significantly higher prevalence of AIDS diagnosis at baseline than the other groups (P < .0001). A Cox regression model adjusted for age, HIV transmission mode, country of birth, and alcohol consumption showed a higher relative risk (HR) of progression to FIB-4 >3.25 in HCV+/HBcAb+/HBsAg- patients (HR, 7.2; 95% CI, 3 8–13.64). Conclusions HBcAb+ contributes to liver damage in HIV+/HCV+/HBcAb+/HBsAg- subjects. A careful monitoring for signs of previous HBV infection is needed in this kind of patients.