Brain abscess is an infrequent complication of meningitis, including cases caused by Gram-negative enteric bacteria in neonates. Because brain abscesses recently developed in four of five neonates with Citrobacter diversus meningitis at one institution, we reviewed cases of C diversus meningitis reported in the literature and those enrolled in the Neonatal Meningitis Cooperative Study Groups and reported to the Centers for Disease Control. Seventy-four cases in neonates were identified, and a brain abscess had developed in 41 (77%) of 53 patients for whom the information was available. This high frequency indicates the need for rapid diagnosis of this complication of C diversus meningitis.