The aim of this study was to assess the impact of fatigue on the quality of life of patients with chronic hepatitis C (CHC) and to examine its relationship with various parameters of the disease, including viral load. The Fatigue Impact Scale (FIS), a self-report questionnaire, was applied to 92 patients with CHC, and the results were compared to those of an age-matched cohort of 213 healthy blood donors. Fatigue was frequent and disabling, being present in 67% of CHC patients, and the FIS was significantly increased in CHC patients compared to the healthy controls. Fatigue severity was not correlated with the activity of the disease or with the level of viremia. The FIS proved to be a valuable tool to assess this symptom. It should be of help for better evaluation of the clinical spectrum of the disease and should be included in trials assessing the efficacy of therapeutic interventions.