We describe the case of a 78 year-old man presenting with multiple edematous erythemas, fever, and arthralgia who subsequently developed neutrophil infiltration into the cartilage of the bilateral auricularis, consistent with relapsing polychondritis. A Skin biopsy of the erythema on his right arm showed dense neutrophilic infiltration into the dermis, while a bone marrow aspirate revealed myelodysplastic syndromes with characteristic vacuoles in myeloid precursor cells. Although the patient achieved remission with high-dose oral prednisolone, the inflammatory symptoms relapsed, and he was resistant to colchicine and cyclosporine. The patient spontaneously developed left leg edema and high-output cardiac failure caused by an arteriovenous fistula with a common iliac artery aneurysm. We successfully performed a two-stage surgery using internal iliac artery coil embolization and endovascular aortic repair of the iliac aneurysm. We assumed the patient was suffering from large-vessel vasculitis such as giant cell arteritis or Takayasu arteritis. We treated him with tocilizumab in addition to prednisolone, and the febrile events and elevated C-reactive protein levels improved. One year later, sequencing of ubiquitylation initiating E1 enzyme (UBA1) using peripheral blood leukocytes revealed somatic variants (c.121A > C p.Met41Leu), confirming the diagnosis of vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome. This case suggests that arteriovenous fistula could be a complication of VEXAS syndrome with large-vessel vasculitis, and adequate surgical intervention and prompt diagnosis are essential for rescue. Although arteriovenous fistula is a rare complication of VEXAS syndrome, physicians should be aware of this complication to ensure prompt diagnosis and timely surgical intervention.