OBJECTIVE: To study the role of NF-κB signal pathway in neonatal rats with sepsis so as to provide the experimental base for corresponding clinical treatment of sepsis, in which NF-icB is taken as the target. METHODS: The sepsis model was established by injecting staphylococcus aureus subcutaneously in 10-day-old newborn rats. The activity of NF-icB in the lungs of newborn rats with staphylococcus aureus sepsis was detected by the electrophoretic mobility shift assay (EMSA) and the effect of anti-oxidant pyrrolidine dithiocarbamate (PDTC) on it was studied. RESULTS: In newborn rats with staphylococcus aureus sepsis, the activity of lung NF-κB was enhanced at the 1st h and reached a peak at the 3rd h after injection of staphylococcus aureus. PDTC had an inhibitive effect on the activity of lung NF-κB. The larger the dosage, the more intensified the inhibitive effect. CONCLUSIONS: In newborn rats with staphylococcus aureus sepsis, the NF-κB of lungs is activated, and the activation of NF-κB has a peak. The anti-oxidant PDTC can inhibit lung NF-κB activity in a dose-effect way in newborn rats with staphylococcus aureus sepsis.