[Objective]To study the effect of semi-constrained total elbow arthroplasty in rheumatoid elbow arthritis.[Method]Eighteen semi-constrained total elbow replacements were performed on 22 rheumatoid patients with 28 elbows(Morrey Stage:6 of Ⅲ Stage,17 of Ⅳ Stage,5 of Ⅴ Stage).The elbows were reviewed retrospectively after a followup of mean 26 months(range12~44 months).Mayo Elbow Performance was used to evalue the function of preoperative and postoperative elbow.The curative effect and complications were observed.The statistically significant differences were analyzed.[Result]Elbow arthroplasty was successful in 22 rheumatoid patients with 28 elbows.After 6 weeks function exercise the Mayo Elbow Performance was improved from(31.6?29.2)to(82.1?24.3)with a statistically significant difference(P