Key words: SalmonellaEnteritidis, Disinfectants, TH4,Virkon-S, Povidone Iodine, Norfloxacin Salmonella enterica serovar Enteriditis (S.Enteritidis) is a food borne pathogen of human causing food-poisoning and sometime deaths. Many methods have been carried out to decrease the population and prevalence of the causative agent, including chemotherapy and disinfection. In this study, in vitro combination between chemotherapy and disinfection was carried out. Three disinfectants [TH4® (combination of quaternary ammonium compound and gluteraldhyde), Povidone Iodine®(iodophore) and Virkon® S(peroxygen compound)] were tested in vitro against S.Enteritidis. The effect of disinfectants, concentration and time of exposure on the survival of S.Enteritidis was investigated.TH4 0.5% (w/v), Virkon S 1% (w/v) and Povidone iodine7.5%(w/v) reduced S. Enteritidis by 99.9%,72% and 87%, respectively. Further, as the disinfectants' concentration decreased, the survival of bacteria increased. Virkon S and Povidone Iodine recorded satisfied result at 10 min exposure time. TH4 recorded high results at 30 min exposure time. The in vitro combination between the three disinfectants and Norfloxacin 10% showed improvement of the inhibitory effect of TH4 and Povidone Iodine, while the inhibitory effect of Virkon S decreased. In addition, formation of macroscopically white precipitation, which interfere with effect of the two (Virkon S and norfloxacin 10%) and lead to bad inhibitory effect on S. Enteritidis.