Abstract: To investigate the effects of administering fermented milk with live Bifidobacterium lactis Y6 on intestinal health in people with digestive dysfunction, a dietary intervention experiment was conducted. Volunteers with digestive problems were selected to consume 200 mL Y6 fermented milk daily for 4 weeks. Clinical scores were performed before and after the intervention, the Illumina PE300 sequencing platform was used to perform high-throughput sequencing of 16S rDNA PCR product fragments of fecal microorganisms in volunteers, the content of short-chain fatty acids (SCFAs) in feces was determined using gas chromatography. The results showed that drinking Y6 fermented milk had a significant improvement on clinical symptoms caused by digestive dysfunction (P<0.01). High-throughput sequencing results showed that drinking Y6 fermented milk had significant effect on the composition of gut microbiota rather than the diversity and richness. The relative abundance of beneficial bacteria Akkermansia, Collinse and Erysipelotrichaceae_UCG_003 genera increased while the harmful bacteria Lachnoclostridium genera reduced. The contents of intestinal SCFAs (acetic acid, propionic acid and butyric acid) increased significantly (P<0.05). The intervention of fermented milk with live Bifidobacterium lactis Y6 can significantly improve the intestinal health of people with digestive dysfunction, providing a theoretical basis for the application of Y6 strains.