To observe the efficacy of Fengshi Qutong Capsule on adjuvant-induced arthritis (AA) rats and its possible mechanism.Methods:Male Wistar rats (weighing 180～220 g), with the amount of 72, were divided into six groups randomly: control group, AA group, low, medium, high doses (0.25, 0.5, 1.0 g/kg) of Fengshi Qutong Capsule groups as well as Wantong Jingu Pill (0.3 g/kg) positive control group. Except for the control group, the arthritis was induced by a single injection of 0.1 mL of Freund`s complete adjuvant(FCA) into the palmer subcutaneous tissue of the right hind paw. The second day after the onset of arthritis, all the rats were administrated by drugs once per day for 21 days. The swelling symptom of both hind paws on second, 5th, 8th, 12th, 15th, 18th, 21st, 23rd days were examined; arthritis indexes of non-injected paws were assessed; PMφ function was evaluated; the activity of SOD and the contents of MDA, NO, TNF-α, IL-1β, IL-6 in serum were measured as well as the content of PGE2 in tissue fluid and the hemorheology changes.Results:The swelling symptom in right hind paw and left hind paw were significantly relieved among the Fengshi Qutong Capsule groups, the function of PMφ, the hematocrit and erythrocyte sedimentation rate declined significantly; the SOD activity increased while the contents of MDA, NO, TNF-α, IL-1β, IL-6 in serum significantly decreased; and Fengshi Qutong Capsule can also significantly help decrease the content of PGE2 in inflammatory tissue fluid. Conclusion:Fengshi Qutong Capsule shows satisfactory therapeutic effects on AA rats, its mechanism may be related to the inhibition of PMφ activation, enhancement of the capability of scavenging free radicals, declination of inflammatory elements levels and the improvement of the changes of hemorheology.