Aims To evaluate the efficacy of methotrexate (MTX) in preventing the recurrence of acute anterior uveitis (AAU). Methods This prospective, open, longitudinal study included patients from June 2002 to March 2005 who had either three or more episodes of AAU in the previous year, or a recurrence of AAU within 3 months before starting the trial. We excluded uveitis of infectious origin, masquerade syndromes, and patients with contraindications to MTX. The response criteria were defined as an absence of symptoms and the presence of a normal ophthalmologic examination. The study outcome compared the number of flare-ups of uveitis over an MTX-treated for 1 year to the number of flare-ups of the same group during the previous year without MTX. Results A total of 571 patients with uveitis were evaluated during the period of the study, and 10 fulfilled the inclusion criteria. One patient refused the treatment, and nine completed the study. The mean number of recurrences in the pre-MTX year was 3.4 (SD: 0.52), which was significantly reduced to 0.89 (SD: 1.17) in the year of treatment (P ¼ 0.011). Conclusion MTX treatment seems to reduce the number of flare-ups in patients with recurrent AAU.