BACKGROUND: Diabetic nephropathy (DN) is a serious condition that can result in end-stage renal failure. Recent evidence has focused on the dietary effects of polyphenols on blood glucose levels and the complications of diabetes. OBJECTIVES: In this study, we investigated the protective effect of glucosyl hesperidin (G-Hes), composed of glucose and hesperidin, against streptozotocin (STZ)-induced nephropathy in mice. METHODS: We used an STZ-induced diabetic mouse model to investigate the preventive effect of G-Hes on renal pathology. After G-Hes supplementation for 4 weeks, we investigated the renal gene expression profiles using DNA microarray analysis and renal histology to examine the underlying molecular mechanism. RESULTS: G-Hes suppressed the increase in kidney weight without any change in the blood glucose levels. This study identified 511 genes whose expression levels were substantially increased during DN development but were downregulated by G-Hes supplementation. G-Hes prevented mRNA expression associated with renal tubule injury, fibrosis, and immune responses. Notably, G-Hes supplementation considerably decreased the complement component C3 at the mRNA and protein levels in the glomeruli and ameliorated glomerular and mesangial matrix expansion in diabetic nephropathy. CONCLUSIONS: G-Hes supplementation is useful in preventing tubulointerstitial fibrosis and inflammation in a mouse model of DN, without exhibiting a hypoglycemic effect.