Objective：To observe the clinical effect of arthritis prescription for knee osteoarthritis.Methods：Divided 128 cases of patients with knee osteoarthritis who met the inclusion criteria into the observation group and the control group randomly，64 cases in each group.Drugs were administered by a single blind test.The control group was given diacerein capsules for treatment，while the observation group was given arthritis prescription for treatment.The courses of treatment were both three months.Detected the content of interleukin-1β(IL-1β)of synovial fluid in lesioned knees，evaluated pain of knee joint by means of pain visual analogue scale(VAS)，and evaluated relationships between activity and pain and disfunction by using Western Ontario and McMaster University(WOMAC)osteoarthritis index.Respectively observed blood routine，urine routine， stool routine and functions of heart， liver and kidney before treatment and after 3 months of treatment， and recorded gastrointestinal reactions.Results：The total effective rate was 81.25%in the observation group and 82.81%in the control group，difference being insignificant(P＜0.05).After treatment，compared scores of pain VAS and WOMAC osteoarthritis index and content of IL-1β in knee joint fluid in two groups with those before treatment，these indexes all showed an evident decrease，while the flexion and extension range of motion of knee joint was increased，differences being significant(P＜0.05).There were no significant difference being found in the comparisons of those indexes in the two groups(P＜0.05).Conclusion：The therapy of arthritis prescription for knee osteoarthritis has the same clinical effect as diacerein capsules for knee osteoarthritis，and it can delay the progress of this disease and improve the quality of life of patients.