〔Abstract〕 Objective To investigate the effects of linoleic acid(LA) on the diversity and structure of intestinal flora in mice. Methods Twelve SPF grade male C57BL/6J mice at 7 weeks were randomly divided into control group(CTRL group) and linoleic acid group(LA group).One day before the linoleic acid diet was supplemented, the normal food was removed from the LA group and the mice in the LA group were fasted for one night, so that the LA diet was more acceptable to the mice in the LA group, and LA was given on the day of the experiment recording, and the feed was updated at any time to ensure that the mice could eat freely until the end of modeling.After 12 weeks of modeling, mouse feces were collected, and mixed samples were collected for every two mice feces, and then 16sRNA high-throughput sequencing was performed to analyze intestinal flora structure, Alpha and Beta diversity. Results 16sRNA high-throughput sequencing showed that LA intervention damaged the richness and diversity of intestinal flora.The results of principal component analysis showed that the composition of flora in CTRL group was different from that in LA group.At gate level, the relative abundance ofActinobacteriain LA group increased(P<0.01).At the genus level, the relative abundance ofL.Duchenneiin the LA group decreased(P<0.05),but the relative abundance ofBifidobacterium,FaecalibaculumandErysipelotrichaceaein the LA group increased(allP<0.01). Conclusion LA intervention could reduce the richness and diversity of intestinal flora in mice, and adjust the structure of intestinal flora.There were significant differences between beneficial bacteria and pathogenic bacteria in intestinal flora after LA intervention, which provided certain basis for the treatment of bioactive compounds of linoleic acid and the therapeutic adjustment of intestinal microorganisms as targets.