METHODS A possible association between hepatitis C virus infection (HCV) and membranoproliferative glomerulonephritis (MPGN) or membranous glomerulonephritis has recently been reported. The pathogenesis of this entity appears to be immunologically mediated. The purpose of this report is to describe the clinical, laboratory, and histopathological features of three patients with chronic HCV infection, without hepatitis B virus disease or autoimmune diseases, but with glomerular disease. RESULTS All three patients had chronic hepatopathy stigmata, ascitis, peripheral edema, and normal blood pressure values. Laboratory results showed mild liver function abnormalities and normal levels of blood nitrogenous waste products. Microscopic hematuria, hypoalbuminemia, and variable proteinuria without hypercholesterolemia were found in all cases. All three had positive rheumatoid factor. Only one patient had positive antinuclear antibodies and antimitochondrial antibodies at low levels, and another displayed low C3 and C4 serum levels. Renal histology in the three cases showed type I membranoproliferative glomerulonephritis and hepatic cirrhosis in the liver biopsy. CONCLUSIONS This report supports the association between chronic HCV infection and membranoproliferative glomerulonephritis. However, further studies are needed to establish more firmly the association as well as the mechanisms of pathogenesis and causality between them.