Objective-To study the association between the occurrence of peripheral arthritis and of acute anterior uveitis during the course of ankylosing spondylitis (AS). Methods-Retrospective clinical follow up by both chart review and direct patient interview was performed on 271 individuals comprised of 222 local white and 49 Taiwanese individuals with AS. Results-Of 89 white patients with acute anterior uveitis, 36 (40.4%) also had peripheral arthritis, compared with only 33 (24.8%) having peripheral arthritis among the 133 who did not have acute anterior uveitis (p < 0.02). Thirty seven (78.7%) of 49 Taiwanese individuals with AS had peripheral arthritis and these included all 10 patients with acute anterior uveitis from the entire disease cohort (p < 0.05). Conclusions-This cross-sectional survey of AS patients supports the view that patients who develop peripheral arthritis are also more likely to develop acute anterior uveitis.