Objective : Membranous nephropathy(MN) is an organ-specific autoimmune disease and a relatively common cause of nephrotic syndrome in adults worldwide. But treatment of MN is not defined. This study was to evaluate the effects of Acasia Catechu extract(ACE) on the MN induced by cBSA in mice. Methods : Mice were divided into 4 groups. The normal group was injected with a saline solution. The control group was treated with cBSA(10 mg/kg i.p.) only. The third group was treated with cBSA (10 mg/kg i.p.) and ACE (250 mg/kg, p.o.). The fourth group was treated with cBSA (10mg/kg i.p.) and ACE (500mg/kg, p.o.). After cBSA and ACE treatment for 6 weeks, we measured change of body weight, 24hrs proteinuria, serum albumin, total cholesterol, triglyceride, BUN, creatinine, TNF-$\alpha$, IL-6, IL-$1{\beta}$, IFN-$\gamma$, IgA, IgM and IgG levels. The morphologic changes of renal glomeruli were also observed with a light microscope. Results : The levels of 24 hrs proteinuria, total cholesterol, triglyceride, IgG, IgM, IgA, TNF-$\alpha$, IL-6, IL-$1{\beta}$, IFN-$\gamma$ significantly decreased in both ACE groups. The level of albumin significantly increased in both ACE groups. The mRNA expression of IL-$1{\beta}$ in splenocytes considerably decreased in the ACE-500 group. In histological findings of kidney tissue, thickening of GBM decreased in both ACE groups. Conclusions : This study shows that ACE might be effective for treatment of MN. More clinical data and studies are to be done for efficient application.