A 71-year-old woman presented with a high-grade fever, neck pain, anemia and thrombocytopenia. After performing further examinations, we concluded that she had simultaneously developed large vessel vasculitis and myelodysplastic syndrome (MDS). Although glucocorticoid administration improved her clinical symptoms, the MDS transformed into acute myeloid leukemia and she died one year after receiving the diagnosis. The occurrence of immune-mediated disorders in patients with MDS is a well-known phenomenon; however, large vessel vasculitis is a rare complication of MDS. Our case suggests that the association between systemic vasculitis and MDS may result in poor outcomes.