Abstract：Objective：To discuss the effect of extract of cornus officinalis on renal protection and oxidase/reactive oxygen species(ROS)/extracellular signal-regulated kinase(ERK) signaling pathway in rats with chronic renal failure(CRF). Methods：A total of 40 male SD rats were divided into the normal group，the model group，the positive medicine group and the cornus officinalis group， 10 rats in each group. Except for the normal group， the other groups were given gastric perfusion with adenine solution in 0.25 g/(kg · d). All groups were given continuous 21 days for preparing CRF model. After successful modeling，the positive medicine group was given 0.75 g/(kg·d) okra capsules；the cornus officinalis group was given extract of cornus officinalis of 0.60 g/(kg·d)；the normal group and the model group were given normal saline of same volume. The medication was lasted for 28 days. The pathological examination of renal tissues was conducted， and renal tissues were scored；the indexes of the kidney function，and the contents of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) in serum，and associated protein in the kidney were detected. Results：No signs of injury was observed in renal pathology in the normal group；there were lesions including renal glomerular and tubular diffuse atrophy，inflammatory cell infiltration and interstitial fibrosis in the model group； when compared with those in the model group， the three lesions in the positive medicine group were decreased； in the cornus officinalis group， the degree of the three lesions was between the model group and the positive medicine group. When compared with those in the normal group， the inflammation scores， the fibrosis scores，and the contents of blood urea nitrogen(BUN)，Serum creatinine(SCr)，urine protein(UP)， TNF- α， IL-6， α- smooth muscle actin(α- SMA)， NADPH oxidase1(NOX1)， ROS and phosphorylation- ERK(p- ERK) in the model group were increased(P＜0.05)； when compared with those in the model group， the two scores and the nine contents in the positive medicine group and the cornus officinalis group were decreased(P＜0.05)；when compared with those in the positive medicine group，the two scores and the nine contents in the cornus officinalis group were increased(P＜0.05). Conclusion： The extract of cornus officinalis has significant protective effect on CRF rats through inhibiting inflammatory response and fibrosis in renal tissues，whose mechanism is probably related to oxidase/ROS/ERK signaling pathway.