In the present study, in order to clarify the clinicopathological characteristics of MN-FSGS(+) cases, and the mechanism of the development of FSGS lesion in MN, we examined retrospectively the cases of MN with and without FSGS, focusing on the clinical characteristics, glomerular endothelial and capillary injury, thickening of glomerular capillary walls with the accumulation of extracellular matrix (ECM), and the expression of VEGF in podocytes. The gene discussed is VEGFA; the disease is focal segmental glomerulosclerosis.