Dermatomyositis (DM) is an autoimmune disease characterized by subacute-onset proximal symmetric muscle weakness, skin abnormalities, and muscle inflammation. Descriptions of DM as a complication of chronic graft-versus-host disease (cGVHD) are very rare. We report a 50-year-old woman who developed DM associated with cGVHD after allogeneic stem cell transplantation.