Bacillus subtilis，Bacillus cereus，Staphylococcus aureus and Salmonella are common residual spoilage bacteria in food. In order to reduce their pollution on food，MIC，MLC and antibacterial effects of these bio-inhibitors against these four kinds of spoilage bacteria were studied under different concentrations，pH，and with chelating agents in this paper. The results showed that MIC and MLC of ε-PL on these bacteria were all 0.125 g/L except MLC on Salmonella for 0.2 g/L. MIC of Nisin on these four kinds of bacteria were 0.125、0.25、0.25 g/L and 0.5 g/L respectively，MLC of Nisin were 2.5、3.0、2.5 g/L and 3.0 g/L respectively. MIC of CTS on these bacteria were all 0.25 g/L except Salmonella for 0.5 g/L. MLC were all 5.0 g/L except Staphylococcus aureus for 4.0 g/L. The antibacterial effects of bio-inhibitors on these spoilage bacteria were gradually enhanced with increase of concentration. ε-PL had the best antibacterial effects on gram positive and negative bacteria，especially under neutral condition（pH=7）. While Nisin and CTS in acidic condition（pH was 3 or so） had higher antibacterial activity. The bio-inhibitors compounded with EDTA had obvious synergistic antibacterial effects，which was the best in ε-PL and EDTA.
