Bifidobacterium lactis (Bifidobacterium lactis) TCI604 and applications of the Bifidobacterium lactis TCI604 and its metabolites, wherein the Bifidobacterium lactis TCI604 is deposited in the German Culture Collection of Microorganisms (the deposit number is DSM33303), and the Bifidobacterium lactis Bacillus TCI604 and its metabolites have the effect of regulating CRP, IL-1β, IL8, IL6, IL10, IL17A, TNF-α, CYP7A1, and APC gene expression, so it can be used to reduce the incidence of colorectal polyps, reduce the incidence of colorectal cancer, reduce The incidence of peptic ulcer, reduce the incidence of gastroesophageal reflux, help digestion, improve gastrointestinal function, regulate immunity, and regulate blood lipids.