The cerebral abscess still occurs in children with cyanotic congenital heart disease. Mortality and morbidity have not yet been reduced in spite of new antibiotics and surgical techniques. We describe our experience with 185 patients having cyanotic congenital heart disease (117 with tetralogy of Fallot, 23 with complete transposition, 9 with tricuspid atresia, 4 with total abnormal venous return, 10 with double-inlet ventricle, 15 with double-outlet right ventricle and 7 with common arterial trunk) who have been followed regularly in our department. Their ages ranged between 3 years and 15 years. During the period of follow-up, cerebral abscess developed in 7 cases. Six of them had tetralogy of Fallot and one had complete transposition. One patient died before surgery could be performed. Operation was carried out in 6 patients and one died in the early postoperative stage. The others were as healthy as could be expected. Alpha-hemolytic streptococcus was isolated from the abscess in one patient, and Enterobacter in another. The abscesses were localized in the occipito-parietal region in 2 cases, the fronto-parietal region in 2 cases, and the parietal, temporal and occipital regions in one case each. Physical examination was normal apart from fever in 5 patients and, in these patients, the cause of fever could not be explained. Neurologic evaluations were all within normal range. If fever occurs unexpectedly in a patient with cyanotic congenital heart disease, therefore, it is important to rule out the possibility of a cerebral abscess.