Thymus pentapeptide is mainly the active ingredient in thymus secretion, there are five amino acids composed of arginine, lysine, aspartic acid, valine, tyrosine five amino acid composition. The main function is to induce the differentiation of immune cells, so that the body’s immunity is strengthened, inducing the occurrence of other immune responses and enhancing the resistance of patients. It can be applied to malignant tumors, after radiotherapy and chemotherapy, the immune function is damaged, need to rebuild the immune system of the patients, as well as the treatment of hepatitis B and C. If it is a major surgical operation as well as serious infections of the patients, it can be used to thymic pentapeptide to enhance the immunity of the patients and rebuild the immune system. It can also be applied to certain autoimmune diseases, such as rheumatism, rheumatoid, type 2 diabetes, lupus erythematosus and other immunocompromised people.