PURPOSE: Neonatal seizures are the most frequent major manifestation of neonatal neurologic disorders. The goal of this study is to help understanding neonatal seizure by analysis of etiology, clinical manifestation, method of diagnosis and prognosis. METHODS: Retrospective reviews were made on 73 cases of neonatal seizure who were admitted to the neonatal intensive care unit, Dongkang General Hospital for 4 years from March 1994 to February 1998. RESULTS AND CONCLUSION:1) Male to female ratio were 2.5 : 1.2) According to the gestational period, preterm babies were 11.0%, postterm babies were 2.7%, and term babies were 86.3%3) The causes of neonatal seizures were hypoxic ischemic encephalopathy (32.9%), hypocalcemia (20.5%), hypoglycemia (9.6%), sepsis (96%), benign idiopathic neonatal seizure (6.8%), intracerebral hemorrhage(5.5%), hyponatremia(1.4%), hypernatremia(1.4%), kernicterus, hyperammonemia, in order of frequency 4) The onset of neonatal seizures were within 24 hours of postnatal age in 21 cases (28.8%), on second and third days in 34.2%, and between fourth and seventh days in 13.7%. 5) The types of neonatal seizures were subtle (39.7%), generalized tonic (27.4%), focal clonic (16.4%), multifocal clonic (13.7%), focal tonic (4.1%), and myoclonic (2.8%), in order of frequency.6) The electroencephalographies were performed in 29 cases and showed abnormal findings in 16 cases (55.2%).7) The ultrasonograms were performed in 12 cases. Abnormal findings were detected in 50% of the patients, and the findings were periventrcular leukomalacias in 4 cases, intraventricular hemorrhage in 1 case, intracerebral hemorrhage in 1 case. The brain computed tomographies were done in 23 cases, and 8 patients showed abnormal findings; diffuse cerebral ischemia in 5 cases, focal cerebral ischemia in 2 cases, subdural hemorrhage in 1 case. The brain magnetic resonance imagings were done in 6 cases, and 3 patients showed abnormal findings; diffuse cerebral ischemia in 2 cases, corpus callosal agenesis in 1 case.8) Fifty six patients (76.7%) were discharged in improved state, 3 patients (4.1%) were discharged against medical advice, 2 patients (2.7%) were transfered other hospital, and 12 patients (16.5%) were expired.9) The follow-up examination were made on 44 cases (78.6%) during the period from 5 days to 30 months of age, and 10 cases showed neurologic sequalae; recurrent seizures in 5 cases, cerebral palsy in 5 cases, and other conbined eurologic sequalae in 4 cases.