Cutaneous arteritis (CA) is a rare cutaneous manifestation of Crohn's disease. A 50-year-old woman with a 15-year history of CA was admitted to our hospital with a fever, abdominal pain, and hematochezia. Based on these symptoms and increased C-reactive protein levels, systemic vasculitis was considered. However, emergency colonoscopy revealed multiple longitudinal ulcers throughout the colon, thus suggesting Crohn's disease. Prednisolone (60 mg/day) was administered intravenously. A histopathological examination of the biopsied colonic mucosa revealed epithelioid granulomas, which confirmed the diagnosis of Crohn's disease. Because the systemic evolution of CA is rare, other comorbidities should be considered when patients with CA experience systemic manifestations.