This study included fifty two premature babies in whom EEG was performed at National Medical Center, from Jan. 1990 to Jun. 1991. clinical and EEG records of all subjects were analyzed and the following results were obtained. 1) The day of first EEG performed were;11 cases within 10 days, 20 cases from 11 days to days, 13 cases from 21 days to 30 days and 8 cases beyond 31 days. 2) The results of first EEG were; within normal limit in 34 cases, mild abnormality in 3 cases, moderate abnormality in 11 cases and marked abnormality in 4 cases. 3) The abnormal EEG ratio according to the sex was higher in female than in male (43.5% vs 27.6%). 4) The abnormal EEG ratio according to the gestational age was higher in shorter gestational age group than in longer gestational age group (40.9% under 32 weeks of G.A. vs 30.0% beyond 33 weeks of G.A.). 5) The abnormal EEG ratio according to the birth weight was not significant. 6) The abnormal EEG ratio according to the ventilator use was higher in used group than in not used group (38.5% vs 30.8%). 7) Combined diseases in 18 cases of abnormal EEG group were jaundice (14 cases), hyaline membrane disease (7 cases), asphyxia (4 cases), anemia (4 cases), hydrocephalus, sepsis, PDA, hypocalcemia, UTI and IVH. 8) The mean apgar score in abnormal EEG group was lower than normal EEG group both in one minute and five minute. 9) Two cases among 18 cases of abnormal EEG group showed abnormal brain sonographic findings, but one case among 34 cases of normal EEG group showed abnormal brain sonographic finding. 10) Ten cases were followed up with serial EEG, six cases of which were treated with anticonvulsant. We observed normalization of the EEG in 5 cases of anticonvulsant treated group.