OBJECTIVE To evaluate radiologic progression in patients with early rheumatoid arthritis (RA) receiving methotrexate (MTX) as the first slow acting drug. METHODS An open, prospective study of 29 patients with RA (21 F, 8 M, mean age 48.5+/-15.4 yrs). The mean duration of RA was 6.6 (2-60) months; and rheumatoid factor was present in 11 cases. Clinical, biological, and radiographic evaluations were done before the start of MTX treatment and after 13+/-3.8 months. Radiographs of hands and wrists were blindly studied by 2 physicians, using Larsen's and modified Sharp's methods. There was a significant correlation for the scores of the 2 physicians evaluated by kappa coefficient. Radiographic evolution was defined as an increase of 15 points in the radiologic score by each method used. RESULTS Patients showed significant clinical improvement after one year of MTX treatment. Despite clinical and biological improvement, significant mean radiographic progression was noted, with Larsen's method (p = 0.001) and Sharp's method (p = 0.034), without reaching the maximum score. However, using the definition of radiographic progression, the radiologic scores indicated stabilization in 23 patients with Larsen's method and in 24 patients with Sharp's method. CONCLUSIONS This study revealed mild radiographic progression in early RA patients treated with MTX for one year. Further controlled studies are needed.