Objective To study the clinical effect of total knee arthroplasty for severe osteoarthritis of the knee.Methods 25 patients with osteoarthritis (30 knees) had been performed to total knee arthroplasty (TKA),and analyzed by HSS knee score system.The average follow-up time was 27 months.Results All patient acquired excellent improvement in pain,function and range of motion (ROM),especially in pain improvement.Among the general evaluation there were 25 best knees (83.3%),3 better knees (10%),2 poor (6.6%).The excellent rate was 93.3%.Among them,2 case occured deep venousthrombosis.Conclusion TKA is an execellent method in the treatment of severe osteoarthritis.