Lymphoproliferative disorders associated with hepatitis C virus (HCV) make up a heterogeneous group of diseases, including lymphomas. It was only recently that HCV was recognised as being a potential cause for the development of non-Hodgkin's lymphoma. The authors report a case of an older woman with chronic hepatitis C who developed primary spleen lymphoma. This case report points out the pathophysiological mechanisms of this disease and the importance of considering this disease in the differential diagnosis of patients with chronic HCV infection.