We describe herein the clinical courses and outcomes of 26 patients who received oral mycophenolate mofetil (MMF) for the treatment of steroid-resistant refractory or steroid-dependent acute or chronic graft-versus-host disease (GVHD) in a single institution. In most cases, 1,500 mg/day of MMF is a median dose (range 500-3,000 mg/day) and administered for 116.5 days (range 9-584 days) along with calcineurin inhibitors and steroids. Although 20 patients (77%) showed rapid improvement of GVHD symptoms, of 15 patients, 13 (87%) showed acute GVHD; of 11 patients, 7 (64%) showed chronic GVHD; most patients (54%) experienced infection during MMF administration, including 5 cases with life-threatening infection. Positive cytomegalovirus (CMV) antigenemia was also observed in 19 patients (73%), but no patients developed CMV infection. Within the median follow-up of 12.5 months (range 0.5-67 months), 10 patients (39%) died. This small study demonstrates that MMF offers an alternative tool for rescuing steroid-refractory or steroid-dependent GVHD, but increases the risk of developing life-threatening infection.