The effects of placenta polypeptide injection are mainly to enhance the immune function of cells, inhibit the peroxidation reaction of the body, scavenge free radicals, and also inhibit mutation, and have repairing effect for DNA, and also increase the ability of bone marrow hematopoiesis, these are the effects of placenta polypeptide injection. It can be applied to improve the immunity of human body in the clinic, and it can be used to treat some diseases, such as viral infection and leukopenia caused by various reasons, and it can also help to heal the wounds after surgery. Placental polypeptide is mainly injected intramuscularly or intravenously in the clinic and should be used under the guidance of a doctor.