Objective: To screen a strain of lactic acid bacteria(LAB) from traditional Sichuan pickles with the best antibacterial activity against Listeria monocytogenes, and to investigate its antibacterial substances. Methods: The Oxford cup and drilling method were used to screen a strain of LAB9 with the best inhibitory effect on Listeria monocytogenes. Bacterial identification was done through 16S rDNA gene sequencing. The minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) were determined using the dilution ratio method. Preliminary analysis of antibacterial substances was performed through organic acid exclusion assay, protease, acid-base and heat sensitivity tests. To investigate bacteriocin encoding gene, polymerase chain reaction(PCPF-6463922体内实验剂量R) was performed by specific primers. Then, its drug resistance and safety were evaluated. Results: LAB9 was identified as Lactobacillus plantarum. The diameter of antibacterial circles of LAB9 against L. monocytogenes were measured to be 19.85 ± 0.14 mm and 11.84 ± 0.16 mm by two inhibition assays. The MIC and MBC of LAB9 were 4 mg/ml and 32 mg/ml, respeBYL719ctively. According to preliminary investigations, antibacterial substances were mainly bacteriocinbioimage analysiss, although the effect of organic acids cannot be excluded. The PCR detection of several bacteriocin coding genes revealed that LAB9 was harboured six bacteriocin gene among the tested genes, including PLNJK, plnW, plnEF, plnA, plnQ, nis, and plnXY. Among the seven commonly tested antibiotics, only gentamicin and vancomycin showed tolerable effects on the strain. In addition, LAB9 did not exhibit hemolytic activity. Conclusion: This study screened a strain of Lactobacillus plantarum LAB9 that produces bacteriocins but does not exclude organic acids, and exhibits strong inhibitory effects on Listeria monocytogenes. These findings provide a valuable foundation for the control of Listeria monocytogenes at low temperatures and the development of novel antimicrobial drugs suitable for application in the food industry.