The purpose of this study was to determine the frequency of liver involvement in malignant lymphomas. Non-specific liver changes were also registered. Percutaneous liver biopsy was performed on 120 patients with untreated malignant lymphomas. There were 38 patients with Hodgkin's disease, 42 with histiocytic and 40 with lymphocytic lymphomas. All the biopsy specimens were histologically and cytologically analyzed. Positive liver findings (lymphomatous infiltration) were observed in 27.5% of patients with lymphocytic, 23.8% with histiocytic lymphomas, and 7.8% with Hodgkin's disease. Liver involvement in non-Hodgkin's lymphomas was significantly higher (P less than 0.025) than in Hodgkin's disease. In the whole group of patients, there were non-specific liver changes: 23 chronic persistent hepatitis, 5 aggressive hepatitis, 9 liver steatosis and 4 liver hemosiderosis. Based on these results, it can be concluded that liver involvement with lymphomatous tissue is more common in non-Hodgkin's lymphomas. Knowledge of this is relevant for clinical staging and the treatment program. These findings also confirm that percutaneous liver biopsy is a valuable diagnostic procedure in the staging of malignant lymphomas.