Over the past 2 decades considerable evidence has accumulated on the association between hepatitis C virus (HCV) and hepatitis B virus (HBV) and several hematologic malignancies, most notably B-cell non-Hodgkin lymphoma (NHL). In this review we summarize this evidence, address possible mechanisms whereby hepatitis viruses may contribute to lymphomagenesis, and discuss the therapeutic fallouts from this knowledge. Most of this evidence is on HCV, and this is the main focus of the review. Moreover, we mainly address the association with NHL, the most prevalent hematologic malignancy, and the most extensively investigated with regard to an association with hepatitis viruses. Available evidence on the association with other hematologic malignancies is also addressed briefly.