Background: H 2 S plays critical roles in the pathogenesis of chronic kidney diseases. Results: H 2 S improved renal function and attenuated glomerular basement membrane thickening, mesangial matrix deposition, and renal interstitial fibrosis in diabetic rats. Conclusion: H 2 S attenuates oxidative stress and inflammation, reduces mesangial cell proliferation, and inhibits the reninangiotensin system in diabetic kidney. Significance: H 2 S alleviates the development of diabetic nephropathy.