The inhibitory effect of antimicrobial peptide LFcin(17-30) on methicillin-resistant Staphylococcus aureus (MRSA) biofilm was studied. Methods: MRSA in 24 strains of Staphylococcus aureus were screened by PCR and cefoxitin disk diffusion method. The biofilm-positive strains were identified by Congo red plate method and crystal violet staining method， and the biofilm-forming ability and biofilm growth curve of biofilm-positive strains were evaluated. The relationship between MRSA biofilm and drug resistance was verified by disk diffusion method. The minimal inhibitory concentration(MIC) of LFcin(17-30) against MRSA was determined by microdilution method. The inhibitory effect of LFcin (17-30) on MRSA biofilm was determined by crystal violet staining and scanning electron microscopy (SEM). The effect of LFcin (17-30) biofilm composition was determined. The results showed that 4 strains of MRSA were screened out from 24 strains of Staphylococcus aureus， which were DQ05， DQ07， DQ09 and DQ23， and the biofilm was identified as biofilm positive strains. The results of crystal violet staining showed that DQ05 had the strongest membrane production ability among the four MRSA strains， DQ09 had the weakest membrane production ability， and the drug resistance of DQ05 was stronger than that of DQ09. The biofilm growth curve showed that the amount of biofilm was the highest at 24 h. The MIC of LFcin (17-30) against MRSA was 150 μmol/L. LFcin (17-30) at 75 μmol/L can significantly inhibit the formation and destruction of biofilms. LFcin (17-30) inhibited the synthesis and secretion of extracellular polysaccharides and extracellular proteins in extracellular polymers， and the effect on extracellular DNA increased with the increase of LFcin (17-30) concentration. In summary， LFcin (17-30) can inhibit the prevalence of food-borne MRSA strains and biofilm formation， and is expected to be used as an adjuvant therapy for food-borne MRSA.

LFcin (17-30)  /  antimicrobial peptides  /  methicillin-resistant Staphylococcus aureus  /  biofilm