Thirty-three patients with II type mixed essential cryoglobulinemia (MEG) were randomized into two groups: one to receive combined therapy including prednisone plus interferon, the other to receive prednisone therapy. Interferon was administered as induction treatment (3 Mu/day) and then as maintenance therapy (3 Mu three times a week). 83% of the combined therapy patients responded as opposed to 27% of the prednisone treated patients. Among the patients that responded to combined therapy, nine of them had a complete response, four a partial response, and two a minor response. None of the patients treated with prednisone therapy responded completely but only two had a partial and two a minor response. Four patients (three of combined therapy and one of prednisone therapy) showed proteinuria before the treatment which improved at the end of the induction therapy. Ten patients showed anti-HCV positivity which remained unchanged after the treatment. Three patients showed liver involvement secondary to cryoglobulinemia and an improvement of histological pattern after the induction with combined therapy. One patient showed an improvement of peripheral neuropathy after induction with the combined therapy. These data suggest the effectiveness of interferon given as induction and as maintenance treatment in the therapy of II type mixed essential cryoglobulinemia.