To evaluate the features of clinical presentation of neonatal necrotizing enterocolitis and its associated factors.Retrospective study of the cases of neonatal necrotizing enterocolitis (n = 56) diagnosed at Neonatal Intensive Care Unit Lagoa (NICU), between December 1986 and July 1992. Diagnosis and stages of the disease followed the modified Bell's criteria. Diagnosis and follow-up of all cases were evaluated. The cases of enterocolitis - degrees II and III (n = 44) - were subsequently selected and compared to a case-control group (n = 44), selected according to birthweight (+/- 250 g) and hospitalization period (+/- 2 weeks). The statistically significant analysis was considered as p < 0.05.Out of 2,447 newborns admitted to the NICU, 56 (2.3%) presented enterocolitis. Mean weight was 1908.5 g; mean gestational age was 35 weeks and 1 day; mean period for diagnosis was 10.7 days; 51 (91.1%) patients were fed before diagnosis; 18 (32.1%) needed urgent surgery; nine (16.9%) hemocultures were positive; 10 (17.8%) patients died. Four clinical standards were observed: fulminant, acute with pneumatosis, insidious and suspect. Comparatively to the case-control group, three factors were significantly associated with enterocolitis: apnea (p = 0.045), rapid increase of food intake (< 20 ml/kg/day) - (p = 0.048) and presence of infectious agent (p = 0.000).Significant factors associated with enterocolitis were occurrence of apnea, rapid increase of food intake and identification of the infectious agent.