To investigate the significance of liver biopsy in children with nephrotic syndrome,liver and renal biopsy samples were simultaneously examined with light microscopy,elctronic microscopy,and immunofluorescence in 10 patients. The results showed that all patients had abnormal liver histologic changes.Focal fatty degeneration in liver tissue was found under microscopic examination,and cytolysis and mild fatty degeneration were found in hepatocytes under electronic microscopic examination.The results suggested that disorder of lipid metabolism not only was toxic to glomeruli, but also deleterious to hepatocytes,then in turn enhanced abnormality in lipid metabolism. It is believed that hyperlipidemia is related to an increased anabolism of lipid and apolipoprotein, and reduction in catabolism of chylomicron and very low density lipoprotein .Therefore, with treatment of hyperlipidemia in these patients, it is possible to arrest progressive renal injury.