To determine whether the risk of infectious complications after total joint arthroplasty is increased in rheumatoid arthritis patients who are treated continuously with leflunomide, the incidences of infectious complications in 41 rheumatoid arthritis patients who received continuous leflunomide treatment (leflunomide group) and in 41 patients who did not receive leflunomide within 4 weeks of surgery (nonleflunomide group) were compared. The incidence (6.1%) of local infection after surgery in the leflunomide group (82 procedures) was slightly lower than that (6.3%) in the nonleflunomide group (79 procedures). There were no systemic or deep infections. None of the other variables analyzed were identified as risk factors for postoperative complications. The results indicate that there is no dramatically increased risk of postoperative infectious complications in rheumatoid arthritis patients who continue to be treated with low doses of leflunomide perioperatively.