Abstract: Many studies found that probiotics have immunomodulatory effects,and involved in the development of various diseases,such as inflammatory diseases and tumor. Probiotics and their metabolites participate in macrophage polarization,regulate mucosal barrier function and immune balance,promote the reconstruction of immune micro-ecological environment so as to achieve the purpose of adjuvant treatment of various diseases. This article discusses the anti-tumor immune effects of probiotics on digestive system,respiratory system,motor system,reproductive system,immune cells,metabolism and interaction with immune checkpoints. It would provide some research ideas for the mechanism of probiotics and their metabolites fermented from local characteristic dairy products in regulating immunity,anti-tumor,enhancing the activity of chemotherapy drugs and protecting intestinal mucosal barrier.