This study aims to determine the effectiveness of mycophenolate sodium (MS) in patients with scleroderma (SSc)-related interstitial lung disease (ILD). In a prospective observational study, we evaluated 14 consecutive SSc-ILD patients who were treated with MS for 12 months. The effect of MS on lung function was examined by using longitudinal data analytic methods. Wilcoxon rank-sum tests were used to examine the forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and diffusing capacity of the lung for carbon monoxide (DLCO) by pulmonary function testing. As a group, the median values for FVC, FEV1 and DLCO did not change significantly after 12 months of MS therapy and fulfilled the definition of stable disease by the American Thoracic Society. Individually, after 12 months of treatment, 6 out of 14 patients showed a pulmonary improvement defined as an increase of more than 10% in FVC, and 5 out of 14 patients remained stable. By contrast, the median FVC had declined a non-significant 7.2% from the previous 12 months before MS initiation. No significant drug adverse effects were registered. These prospective data suggest that MS is a safe and well-tolerated therapy for SSc-ILD patients, and it is capable of preventing functional pulmonary deterioration.