The podocyte is regarded as a highly differentiated cell with a very limited capacity for mitosis or repair after cell damage or excessive tuft enlargement. When podocytes are injured, they are not able to repair themselves by replication as glomerular mesangial cells or endothelial cells do. In this study, we carried out a morphometric analysis of glomeruli on PAS-stained renal sections from 27 patients with IgA nephropathy, and discussed the relationship between the morphometric parameters and the clinical data, i.e., urinary protein excretion, serum creatinine, and creatinine clearance at the time of renal biopsy. It was evident that the areas of glomerular capillary walls covered by one podocyte were significantly increased and were inversely correlated with creatinine clearance. Podocyte damage might be correlated with the progression of glomerulosclerosis in patients with IgA nephropathy. It is assumed that the maladaptive changes of podocytes will result in the onset and development of glomerulosclerosis.