The aim of the study was to determine the etiology of meningitis and sepsis in the newborn at the State University Hospital of Haiti and evaluate the susceptibility 'in vitro' of the pathogens to the antibiotics commonly used. This was a prospective case series study over a 10-month period (May 1997-February 1998) of 42 newborns with sepsis and/or meningitis. Besides the clinical signs, a positive blood culture and/or a positive culture of cerebrospinal fluid was present in each case. Gram-negative bacteria were most commonly found as a cause of early onset sepsis, with Enterobacter aerogenes as the most common agent. There were no such difference between gram-negative and gram-positive in late onset sepsis. Group B Streptococcus was associated with neonatal meningitis (44 per cent of cases) which was more related to gram-positive bacteria (66 per cent). Risk factors were vaginal discharge and dysuria in mothers, and low apgar score in newborns. Thirty-three per cent of the pathogens found, among them Klebsiella pneumoniae, were resistant 'in vitro' to ampicillin and gentamycin. All were susceptible to amikacin. Enterobacter aerogenes is an important pathogen in the etiology of early onset sepsis in the newborn at the State University Hospital of Haiti, while Group B Streptococcus is the leading cause of meningitis in that age group. Resistance to gentamycin should be taken into consideration for the treatment of sepsis and meningitis in the newborn.