OBJECTIVE：To study the improvement effect and possible mechanism of Leontopodium leontopodioides combined with Astragalus membranaceus on the renal function of mesangial proliferative glomerulonephritis （MsPGN） model rats. METHODS：Totally 85 rats were randomly divided into sham operation group （n＝10）and modeling group （n＝75）. Sham operation group underwent sham operation ，and MsPGN model was induced by immunological method [Freund ’s adjuvant+BSA + lipopolysaccharide（LPS）] in modeling group. After successfully modeling ，70 rats were randomly divided into model group ，L. leontopodioides+A. membranaceus high-dose，medium-dose and low-dose groups （4.05，2.03，1.02 g/kg，by total crude drug ），L. leontopodioides alone group （2.70 g/kg，by crude drug ），Tripterygium glycosides tablet group （positive control 1，0.02 g/kg）， Lotensin tablet group （positive control 2，0.02 g/kg），with 10 rats in each group. Sham operation group and model group were given constant volume of normal saline intragastrically ； administration groups were given relevant drug solution intrasgastrcially at a volume of 15 mL/kg，once a day ，for consecutive 5 weeks. At last administration ，24 h urinary lnzyxyqy2003@163.com protein，urine creatinine and serum creatinine were determined in rats. The right kidney was weighed ，and HE staining was used to observe the pathomorpholog y changes of renal tissue. Immunohistochemistry was used to detect the protein expression of NF-κB p65 in renal tissue. Western blotting assay was used to determine the protein expressions of NF-κB p65，IκBα，ERK，p-ERK and p 38 MAPK in renal tissue. RESULTS ：Compared with sham operation group ，right kidney weight ，24 h urine protein and serum creatinine levels ，protein expressions of NF-κB p65， p-ERK and p 38 MAPK in renal tissue were increased significantly in model group （P＜0.05 or P＜0.01）；the level of urine creatinine and protein expression of IκBα in renal tissue were decreased significantly（P＜0.05 or P＜0.01）；there were obvious glomerular hypertrophy ，diffuse increase of mesangial cells ，necrosis of renal tubules and other pathomorphological changes in renal tissue. Compared with model group ，right kidney weight and serum creatinine level were decreased significantly in L. leontopodioides alone group （P＜0.05），while urine creatinine level was increased significantly （P＜0.05），but there was no statistical significance in the level of 24 h urine protein （P＞0.05）；the right kidney weight ，24 h urine protein ，serum creatinine level and protein expression levels of NF-κB p65，p-ERK and p38 MAPK in renal tissue were decreased significantly in L. leontopodioides+A. membranaceus high-dose group （P＜0.05），while the urine creatinine level and protein expression level of IκBα in renal tissue were increased significantly （P＜0.05 or P＜0.01）；there was no statistical significance in above indexes in L. leontopodioides+A. membranaceus medium-dose，low-dose groups （P＞0.05）；pathological changes of renal tissue were improved to different extents in administration groups ，especially in L. leontopodioides +A. membranaceus high-dose group. CONCLUSIONS ： High dose of L. leontopodioides +A. membranaceus can improve renal function of MsPGN model rats by inhibiting MAPK/NF-κB signal pathway.