In order to explore the application prospect of phage-derived peptide in food processing chain， SEYT4， a novel phage-derived peptide containing 37 amino acids was selected as the research object and its structural characteristics were analyzed. The common pathogenic bacteria in food processing chain were selected to carry out bactericidal tests under different temperature， salinity and pH to determine the bactericidal spectrum， bactericidal efficiency and bactericidal characteristics of SEYT4. The safety of SEYT4 was evaluated in C57BL/6 female mice， and the efficacy of SEYT4 in removing pathogenic bacteria from the food chain was investigated by simulating pathogen contamination in leafy vegetables and kitchenware. The results showed that： SEYT4 contained a hairpin shaped double α-helical structure with a molecular mass of about 4.5 ku and a theoretical isoelectric point of 9.69. It could eliminate most of the highly toxic and drug-resistant Gram-positive and Gram-negative bacteria with a bactericidal rate as high as 99.99%. It had high activity at different temperatures， and the bactericidal effect was better in neutral and weak alkaline environment but inactivated in high salt environment. There was no hemolysis effect on mice erythrocytes. In the artificial pollution model of coriander， pathogenic bacteria in leaves and washing buffer could be removed about 90.00%， and more than 99.00% of pathogenic bacteria on food contact surface could be removed. The results showed that bacteriophage peptide SEYT4 was a novel antimicrobial peptide with good bactericidal effect and high safety， which could effectively prevent and control the pathogenic bacteria contaminated in food chain and was expected to be a practical disinfectant in food processing chain.