Objective To study the protective effect of curcumin on renal fibrosis in chronic kidney disease (CKD) and explore its possible mechanism of action. Methods Thirty C57BL/6 J mice were randomly divided into a sham-operated control group (NC), 5/6 kidney ligation model group (LIG) and curcumin treatment group (LIG + CUR),with 10 mice in each group. The CKD animal model was prepared according to the modified 5/6 kidney ligation method.The curcumin group was given a curcumin-containing diet (100 mg/ (kg·d) and the other groups were given normal feed.The mice were euthanized after 3 months. The levels of the fibrosis index α-SMA and the Hippo pathway transcriptional activator Yap involved in fibrosis in CKD were determined. Results Renal function tests showed that urea nitrogen (BUN)and serum creatinine (Scr) were significantly increased in the LIG group compared with the NC group, and that the administration of curcumin effectively protected kidney function. H&E, Masson and immunohistochemical staining showed that the LIG kidneys had obvious tubular lesions and some fibrotic changes, and that the degree of fibrosis was significantly reduced after the administration of curcumin ( P <0. 05). The mRNA and protein levels of Yap increased after modeling,and decreased significantly after curcumin treatment ( P <0. 05). Conclusions Curcumin can significantly ameliorate the mouse CKD induced by 5/6 kidney ligation, and its mechanism may be related to a decrease of Yap in the Hippo signaling pathway.