Immunoglobulin G4(IgG4)-related disease is a chronic immune-mediated fibro-inflammatory disorder, characterize by multiple organ infiltration with IgG4-positive plasma cells, storiform fibrosis and obliterative phlebitis or tumefactive lesions. As increasing the case reports of IgG4-related kidney disease, the clinical manifestations, pathologic and radiologic findings have been more clarified. But it is sometimes misdiagnosed as it mimics malignancies. We report a case of a 77-year-old Korean man, diagnosed IgG4-related kidney disease with membranous proliferative glomerulonephritis, presenting a renal pelvic mass suspected of being malignant.