We encountered a 23-year-old woman with allergic granulomatous angiitis (AGA) associated with cerebral infarction, myo-pericarditis, and acute respiratory failure due to extended eosinophilic pneumonia. She underwent emergency treatment at our hospital because of right hemiparesis and impaired consciousness. AGA was suspected because the patient had a history of bronchial asthma accompanied by pulmonary infiltrations with eosinophilia, and presented with diffuse pulmonary infiltrates, pericardial effusion, diffuse hypokinesis of myocardium, cerebral infarction and marked peripheral eosinophlia. Pulmonary eosinophilia was confirmed by examination of broncho-alveolar lavage fluid. Myocardial tissue biopsy specimens revealed fibrous granulation indicative of myocarditis. The patient responded well to corticosteroid therapy.