The 35 newborns with neonatal sepsis admitted to the Neonatal Intensive Care unit of Dong-A University Hospital during 2 years and 6 months from April 1990 to October 1992, and were reviewed on the bases of incidence, clinical manifestations, underlying conditions, etiologic organisms, results or antibiotics sensitivity test and mortality rates. The results were summarized as follows; 1) The incidence of neonatal sepsis was 1.2% and male predominated. Sepsis was more prevalent in premature babies (7.5%) than in full term babies (0.8%). 2) Neonatal sepsis occured more frequently in low birth weight infant below 2500 g(6.3%) than in normal birth weight infant. 3) Underlying conditions associated with neonatal sepsis were as follows; pneumonia (25.7%), HMD (17.1%), urinary tract infection (11.4%), DIC (8.6%). 4) Common clinical manifestations observed in neonatal sepsis were jaundice (45.7%), poor feeding (22.9%), abdominal distension (20.0%), lethargy, convulsion, apnea and diarrhea in order. 5) Blood culture report revealed that gram negative organisms (57.1%) were more frequently associated with neonatal sepsis than gram positive organisms (37.1%). Klebsiella pneumoniae was the most common microorganisms in neonatal sepsis. 6) Vancomycin (100%), cephalothin (84.6%) and chloramphenicol (84.6%) were the sensitive drug to gram positive organisms. Gram negative organisms were sensitive to amikacin (100%), and cephalothin (95%). 7) Overall mortality rate was 17.1% in all patients with neonatal sepsis, 7.7% in gram positive sepsis and 25% in gram negative sepsis. We conclude that the etiologic organisms of neonatal sepsis have been altered, and have to choose appropriate antibiotics which particularly sensitive to these gram negative organisms such as Klebsiella pneumoniae, Pseudomonas aeruginosa, and also have to specify antibiotics according to the predominant organisms of the each institute.