The association between hepatitis C virus (HCV) infection and B-cell non-Hodgkins lymphomas has been demonstrated in epidemiological studies, in particular in highly endemic geographical areas such as Italy, Japan and southern parts of United States. Marginal zone lymphomas are the histotypes that are most frequently associated with HCV infection. The WHO classification comprises extranodal marginal zone B-cell lymphoma of MALT type, splenic marginal zone B-cell lymphoma and nodal marginal zone B-cell lymphoma. Recently, antiviral treatment has been proved to be effective in the treatment of HCV-positive patients with indolent lymphoma, prevalently of marginal zone origin. This is the strongest evidence of a causative link between HCV and lymphomas. Aim of this review is to illustrate the relationship between HCV infection and marginal zone lymphomas and to systematically summarize the data from the therapeutic studies where antiviral treatment with α-interferon with or without ribavirin was employed in patients with marginal zone lymphomas.