Abstract: Different concentrations of terpenoids were added to the Listeria monocytogenes medium,and no steroids were added to the control group. The minimum inhibitory concentration(MIC),colony number,morphology and conductivity of Listeria monocytogenes were determined and analyzed to investigate the antibacterial mechanism of terpenoids in pepper oil against Listeria monocytogenes. Results showed that,the MIC of terpenoids in pepper oil to Listeria monocytogenes was 0.05%. The addition of 0.1% terpenoids could significantly inhibit the growth of Listeria monocytogenes(P<0.05),which made the cell membrane permeability of Listeria monocytogenes changed,and the bacterial contents lost a lot,the bacteria stuck to each other and died. Moreover,the application of terpenoids in pepper oil to the preservation of cold meat could effectively slow down the growth of the total number of colonies,compared with the control group,the total number of colonies exceeded the national standard(6.0 lg CFU/g)after 12 h of cold storage,adding 0.1% terpenoids could keep the total number of colonies at a low level at 24 h. This study explored the antibacterial mechanism of terpenoids in pepper oil against Listeria monocytogenes and used it for the preservation of cold meat,which is beneficial to the development and utilization of pepper oil. It also provides a theoretical basis for its application in the field of meat preservation.