We report here on a case of non-Hodgkin's lymphoma in which liver involvement was the predominant clinical manifestation. A healthy 44-year-old man presented with upper abdominal pain, hepatosplenomegaly, thrombocytopenia, elevated AST, ALT and bilirubin, and marked elevation of lactate dehydrogenase and alkaline phosphatase. The abdominal CT scan showed only diffuse hepatosplenomegaly and uneven contrast enhancement of the spleen without any definite mass of the liver and spleen. US-guided aspiration biopsy of liver and the histologic examination confirmed a diagnosis of non-Hodgkin's lymphoma, the diffuse large B cell type. Bone marrow biopsy showed the infiltration of malignant lymphoma cells. PET-CT showed an increased FDG uptake of the liver, spleen and long bones. The patient was treated with combination regimen of cyclophosphamide, doxorubicin, vincristine and prednisone chemotherapy. Even in the absence of a mass lesion or lymphadenopathy, primary hepatic or hepatosplenic lymphoma should be considered in differential diagnosis of hepatitis or liver cirrhosis, especially for patients with diffuse hepatosplenomegaly and markedly elevated LDH.