We investigated the possible role of coagulase-negative staphylococci in necrotizing enterocolitis. Stool coagulase-negative staphylococci isolated from neonates during an outbreak of rotavirus-associated necrotizing enterocolitis were analyzed by a variety of techniques, including speciation, semiquantitative culturing, antimicrobial susceptibility, plasmid profiling and cytotoxicity assays. No differences were observed between the coagulase-negative staphylococci of symptomatic babies and those of asymptomatic controls.