Objective:To evaluate the efficacy and safety of leflunomide (LEF) in comparison with methotrexate (MTX) in treatment of rheumatoid arthritis (RA).Methods:50 patients with active RA were randomly divided into two groups.The first group received 20 mg daily LEF.The second group received small dose (7.5～10 mg weekly) of MTX.We compared the degree of the morning stiffness and the number of swelling

aching joints and the change of ESR

CRP and RF in RA patients between LEF group and MTX group.Results:The response rate in the LEF group was higher than that in the MTX group 1 month later( P <0.05).The response rate was not different between the LEF group and the MTX group 3 months later ( P >0.05).1 month after therapy

the clinical situation and experimental findings were much ameliorated in LEF group as compared with before ( P <0.05).Significant difference in the clinical manifestations and experimental findings were found between LEF group and MTX group ( P <0.05).3 months after therapy

the clinical situation and experiment findings were much ameliorated in both groups ( P <0.001) .No significant difference in the clinical manifestations and experimental findings were found between LEF group and MTX group ( P > 0.05) . The incidence of adverse events for LEF and MTX groups were 3/30 and 2/20 respectively

and there was no significant difference ( P >0.05).Conclusion:LEF is an effective agent for treatment ofRA with better tolerability

and there are few adverse effects.