Aim: We performed both a retrospective and prospective study to elucidate the types of glomerular diseases present in adults in Lima, Peru. Material and methods: In the retrospective study, we analyzed 1263 renal biopsies over a 10-year period (1985 1995) that were processed at a central reference renal pathology laboratory in Lima. 101 cases were examined in the prospective study. Results: The most common glomerular diseases observed were those due to systemic lupus erythematosus (30.2%), membranoproliferative glomerulonephritis (MPGN, 14.8%), and focal and segmental glomerulosclerosis (FSGS, 13.9%). Although mesangial-proliferative nephritis was observed in 9.5% of cases, IgA nephropathy was rare (0.9%). Examination of the year to year frequency showed that MPGN has tended to decrease in frequency with time whereas FSGS has been increasing. Although there is known to be a high frequency of infections in Peru, only 4.2% of the cases in the retrospective study were associated with infection. Furthermore, in the prospective study, only one case of hepatitis C and no cases of hepatitis B viral infection were detected, including in the 11 cases of MPGN observed. Conclusion: We conclude that the epidemiology of glomerular disease in Lima, Peru, is distinct from most areas of the world, but has similarities to certain regions in Africa, in that MPGN is common whereas IgA nephropathy appears to be rare. Further studies are necessary to elucidate the reasons why the patterns of glomerular disease are different from that observed in other parts of the world.