Objective To investigate the effect of infecting betamethasone dipropionate 5mg/betamethasone disodium hydrogen phosphate 2mg in articular genu cavity on osteoarthritis.Methods 100 patients were randomly divided into two groups, the treatment group and the control group. The treatment group was treated with diprospan,injected into the inside of knuckle. The control group was treated with oral administration NSAIDs. Results In treatment group the rate of amelioration was 84% after one injection,the rate of amelioration was 90% after one course of treatment. Conclusion Injected diprospan into the inside of knuckle could relieve pain of arthritides, improve the function of arthrosis.