Probiotics are live microorganisms which confer a health benefit on the host when administered in adequate amounts. They can be ingested as medications or dietary supplements to help maintain a balance in the microbial environment of the digestive tract. Probiotics can help maintain homeostatic, enhance physical fitness, thereby reducing the adverse effects caused by anti-cancer treatments. Recent studies have shown that probiotics can protect and alleviate radiation-induced intestinal damage by activating anti-apoptotic pathway AKT, activating COX-2 pathway to inhibit inflammatory reaction, protecting intestinal barrier, improving bacterial translocation and regulating intestinal micro-environment. Although relevant clinical trials of probiotics varied in the type of bacteria species, the concentration of live bacteria, and research methods, most of them demonstrated that probiotics could prevent radiation induced intestinal adverse effects. With the continuous improvement of comprehensive treatment of cancer, the survival time of patients has been prolonged. In recent years, how to alleviate the adverse reactions during and after treatment, alleviate the pain caused by treatment, and improve the quality of life has become increasingly prominent. Future research should focus on optimizing the flora configuration and addressing the safety on immunocom promised patients.