Abstract: Objective To develop an enrichment medium for simultaneous culture of Salmonella,Shigellae and Staphy-lococcus aureu.Methods According to the six micro-nutrient requirements,the different components were compared and the components for the enrichment medium were selected.The effect of the enrichment broth was validated with plate count and multiplex PCR methods.Results An enrichment medium(3S) was obtained which could be used to culture Salmonella,Shigellae and Staphylococcus aureu concurrently.When 10 CFU per one milliliter of Salmonella,Shigellae and Staphylococcus aureu were simultaneously added to the 3S and incubated for 12hr at 37℃,the bacteria multiplied at the same speed,and reached 10⁷-10⁸ CFU per one milliliter.Multiplex PCR could be used to produced specific amplicons of expected sizes.Conclusion 3S can be used to enrich Salmonella,Shigellae and Staphylococcus aureu simultaneously and can be applied in rapid detection of the bacteria conveniently.