A 61-year-old male was referred to our hospital for rapidly progressive azotemia. He was also found to have huge vegetation at the aortic valve causing regurgitation. Biochemical examinations revealed the presence of an immunocomplex associated with decreased circulating complements. In biopsy samples from the kidney, we found the presence of fibrillar crescents, proliferation of mesangial cells, increase in extracellular matrix proteins, atrophy of tubules, infiltration of mononuclear cells in the interstitial regions, high density deposits in the mesangial area and mesangial interposition. Since the patient strongly rejected operative treatment by valvular replacement, we continued non-invasive treatment such as hemodialysis and treatment with penicillin G. This transiently improved the condition of the patient, including biochemical data and cardiac function, but there was no reduction in the size of vegetation at the aortic valve and the bacteria responsible for infective endocarditis were not identified. About three months after admission, overt signs of congestive heart failure emerged and the patients was subjected to intensive care with a respirator and hemodynamic monitoring. Although the cardiac function was improved, concomitant severe pneumonia occurred and the patient died of septic shock. Thus, we report a rare case in whom immune complex-mediated glomerulonephritis was associated with infective endocarditis with aortic valve vegetation.