Introduction: Sepsis and meningitis are major causes of neonatal morbidity and mortality. Objective: To identify the prevalence and risk of meningitis in neonates with sepsis due to group B Streptococcus (GBS) and gram-negative bacteria (GNB), and to compare risk factors, clinical and laboratory characteristics. Patients and Method: Cross-sectional study of 30 infants with infections due to GBS and 41 due to BGN. Data were analyzed by Stata® 11.0, using measures of central tendency and dispersion, according to their distribution, to compare differences. Categorical variables were compared using χ2 test or Fisher's Exact Test and associations using prevalence ratios (PR) and odds ratio (OR) with 95% confidence interval. A level of probability of < 0.05 was used as a significance criterion. Results: The prevalence of meningitis among infants with sepsis was 16.9% (95% CI: 7.5-26.3 %). 33.3% (10/30) of sepsis due to GBS was associated with meningitis, while 4.9% (2/40) was associated with GNB, finding a clear connection between sepsis and meningitis in neonates with GBS (OR: 9.5; CI 95%:1.7-94.3). 80% (CI 95%: 44,4-97,5%) of cases of meningitis associated with GBS sepsis occurred in infants older than 72 hours. Conclusion: Meningitis was more common in infants with GBS sepsis, mainly in cases of late-onset sepsis. The association between GNB sepsis and meningitis was less frequent in early sepsis, and was not found in late sepsis.