In summary, we demonstrated that our probiotic powder ameliorated CRC by regulating Bifidobacterium animalis, Clostridium cocleatum, inhibiting Treg cells, promoting the number of IFN-γ+ CD8+ T cells, increasing Th2 cell abundance, inhibiting the expression of TIGIT in Th2 cells, and increasing B cell abundance in the immune microenvironment of CRC, resulting in increased expression of BAX in CRC. This evidence concerns the gene CD8A and colorectal carcinoma.