Radiodermatitis is one of the most familiar complications in tumor radiotherapy which draws a great attention of both physicians and patients. Currently the evaluation of radiodermatitis mainly depends on the doctor's subjective observation. Some objective evaluation methods still need further research. Many factors influence the occurrence and degree of the radiodermatitis which include internal factors and external factors. Medicines are very important means to prevent and treat radiodermitis. Such as, the plant extract including aloe gel, plantoil; the vitamins include vitamin C, vitamin B12 and vitamin E; the creams mainly including hormone creams and Biafine cream; reorganized epidermis growth factor; Chinese herbal medicine, etc. The prevention and therapeatic effects of the above medicines were studied, but the results varied. More valid methods are expected to prevent and treat radiodermatitis.