The invention relates to a preparation method of (
Lactobacillus planetarium subsp.plantarum)Zhang-LL and its 
listeria monocytogene-resistant 
bacteriocin. The preparation method is suitable for preservation and fresh-keeping of meat and meat products, milk and 
milk products, fruits and vegetable, and instant foods. The (
Lactobacillus planetarium subsp.plantarum)Zhang-LL (CGMCC No.6936) is selected from bacon on the Fujian farmer's market. A 
bacteriocin production broth is obtained by 
fermentation of a Zhang-LL strain, and the Zhang-LL strain 
bacteriocin is extracted and purified by a pH-dependent adsorption-
desorption method, a cation exchange 
chromatography and a reversed phase high-performance liquid 
chromatography so that 
titer is improved by 32 times and purity is improved by 36.65 times. The bacteriocin can inhibit a plurality of food-borne 
pathogenic bacteria such as 
listeria monocytogenes, has high bacteriostatic activity, good heat, acid and base stability, can be degraded by human 
protease and is a natural and safe biological 
preservative. The preparation method has the advantages of simple processes, stability, high efficiency, source convenience, low cost and industrial production feasibility.