A 61-year-old man had hypertension with stenosis in the left renal artery. When his fever, abdominal pain, and renal dysfunction progressed, he was admitted to our hospital. He was diagnosed with polyarthritis nodosa. His renal function rapidly deteriorated despite immunosuppressive therapy. His digestive tract perforated twice, and he subsequently died. An autopsy revealed that aortic intimal sarcoma caused stenosis in multiple arteries. Both polyarteritis nodosa and aortic intimal sarcoma are very rare diseases and the diagnoses are very difficult. It is very important to consider these entities when making a differential diagnosis of vasculitis.