Abstract: In order to improve the antibacterial stability of nisin and broaden its application in the food industry, effects of several phosphate, EDTA-Na2 and sodium citrate on the antibacterial activity of nisin were studied. The results showed that phosphate, EDTA-Na2, and sodium citrate had significant protective effect on the antibacterial activity of nisin and the order of the protective effect was as follows:sodium hexametaphosphate>EDTA-Na2>sodium tripolyphosphate>sodium citrate>sodium dihydrogen phosphate>sodium hydrogen phosphate. After heated at pH6. 8 and 121℃ for 20min, the antimicrobial activity of nisin decreased by 7. 25% and 10. 2% with the addition of sodium hexametaphosphate and EDTA-Na2 respectively.