Two patients with cyanotic congenital heart disease (CHD) and erythremia were seen for abrupt onset of focal neurologic deficits and/or seizure without signs of infection or increased intracranial pressure. Clinical features and initial computed tomography (CT) in both cases suggested stroke. Subsequent CT scans demonstrated cerebral abscess, proved at operation. Review of records of patients with CHD at the University of Rochester (NY) Medical Center from 1965 to 1981 disclosed 12 cases with brain abscess but only two cases with aseptic cerebral infarction. All but one patient with abscess were cyanotic. One third of patients with abscess had a clinical picture suggesting stroke. Clinical or radiologic features of half the cases indicated that cerebral infarction may have led to abscess formation. Diagnosis of brain abscess and immediate antibiotic therapy should be strongly considered in patients with cyanotic CHD who suffer a suspected cerebral infarction.