The identification of Food Safety Object( FSO) is one of important methods for risk management of food pathogen. The basic definition and application of FSO were introduced in this paper,and two methods,the traditional one and the new one based on FSO,were compared for risk management. Then the main limit standards of international associations or countries were reviewed according to Listeria monocytogenes in Ready-to-eat Foods. Moreover,combined with exponential dose-response model,the illness-caused numbers of susceptible population was calculated on the basis of different L. monocytogenes limits in ready-to-eat foods. As a conclusion,The FSO value of L.monocytogenes in ready-to-eat foods might be defined as 2 lgCFU / g,or the limit standards should be 100 CFU / g L.monocytogenes in ready-to-eat foods in our country.