Objective To investigate the effects of taurine on advanced glycosylation end products (AGEs) and transciption of transforming growth factor β1(TGF β1) mRNA in renal cortex of streptozotocin induced diabetic rats. Methods After taurine was given to streptozotocin induced diabetic rats for 14 weeks, the expressions of glomerular type Ⅳ collagen (ⅣCol), fibronectin (FN), laminin (LN) and AGEs proteins were examined by immunohistochemical methods. AGEs content in renal cortex was determined by fluorospectrophotometry. TGF β1 mRNA transcription in renal cortex was detected quantitatively by Northern blot analysis. Results Expressions of glomerular ⅣCol, FN and LN proteins were significantly increased in diabetic rats as compared with control animals. Administration of taurine to diabetic rats obviously reduced expressions of these extracelullar matrix (ECM) proteins. Formation of AGEs in glomeruli and AGEs content in renal cortex of diabetic rats were markedly higher than those in control. Taurine treated diabetic rats had a decrease in the formation of AGEs and AGEs content. TGF β1 mRNA transcription in renal cortex was significantly increased in diabetic rats as compared with controls. Taurine treated diabetic rats induced a decrease in TGF β1 mRNA transcription in renal cortex. Conclusion ECM synthesis, AGEs formation and TGF β1 mRNA transcription in kidneys of diabetic rats were significantly increased and inhibition of ECM synthesis by taurine may be linked to its capacity to suppress AGEs formation and TGF β expression.