Objective:Clarify the effect of ultrafine powder of simiaowan on RA rats, and provide experimental basis for clinical medication. Methods:Drugs were administered to AA rats for 21 days respectively with ultrafine powder 0.71g/kg, 0. 18g/kg(low dose group),traditional preparations(coarse powder)2.16g/kg(high dose group), 0.54g/kg(low dose group). The volume of RA rats toes,organ index( spleen and thymus index), serum inflammation factors (SOD, MDA, NO, IL-1β, IL-6) were investigated to make clear the pharmacodynamic action and mec...