Diabetic kidney disease is one of the complications of diabetes,which can progress to end-stage renal disease.In recent years,it has been found that miRNAs have become a research hotspot,with miRNA-21 regulating transforming growth factor β1(TGF-β1)/Smads,phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT),Wnt/β-catenin and other signaling pathways to promote the progress of diabetic kidney disease.Studies have showed that traditional Chinese medicine has a regulatory effect on the expression of miRNA-21 and can target miRNA-21 to regulate TGF-β1/Smads,phosphatase and tensin homolog/PI3K/AKT/mammalian target of rapamycin(mTOR),peroxisome proliferator activated receptors and other signal transduction pathways to trigger signal cascade reactions,which intervene in pathological processes such as fibrosis,inflammation,oxidative stress and autophagy.In this article,the role of miRNA-21 in diabetic kidney disease and the intervention of traditional Chinese medicine were summarized,in order to provide some reference for the treatment of diabetic kidney disease and the development of new drugs.