Can primary immunodeficiency disease, which is a natural and hereditary disease, be treated? I am often asked this question by parents of children born with this disease. As an older pediatric clinician who is often involved in immunology research, I always say with conviction, “Why not? It is important to understand that primary immunodeficiency disease is not an “incurable” disease. It is true that this disease affects the body’s very important immune system and the prognosis is not very promising. However, with the development of medicine, some primary immunodeficiency diseases can be cured, and those that cannot be cured can be alleviated with certain medical treatments to improve the quality of life of the child and prolong his or her life. Children with primary immunodeficiency diseases should receive careful care, including prevention and treatment of infections, better nutrition, and improved correction of immune deficiencies. Children with primary immunodeficiency disease should be appropriately isolated. Whenever possible, children with the disease should have a separate room to avoid exposure to sources of infection, and should be allowed to avoid infected people as soon as they are around. When the child can grow and develop and live more normally after treatment, the child should be encouraged to participate in normal activities as much as possible, such as playing with other children outdoors and joining childcare institutions, so that the child can have the same ability to live as normal people in the future. The child should be given continuous antimicrobials as prophylactic treatment, which will help the child to reduce repeated infections due to immunodeficiency. Once the child develops fever or other manifestations of infection, he/she should be treated promptly and aggressively with drugs that are sensitive to the pathogen. Unlike the treatment of infections in children in general, these children require high doses of anti-infective drugs and a longer course of treatment, sometimes requiring hospital supervision. In addition, immunomodulators and immunostimulants can be used to relieve the clinical symptoms of the child. Vitamin C, antihistamines, levamisole, and bacterial antigen extracts are commonly used, but their effectiveness is hardly certain. Replacement therapy is an important treatment for primary immunodeficiency disorders, which can temporarily relieve the child’s clinical symptoms by supplementing what is lacking according to the immune component deficiency. Intravenous immunoglobulin (IVIG) is an important agent for replacement therapy, and many antibody-deficient diseases can be treated with IVIG to provide complete relief of symptoms and allow the child to achieve normal growth and development. It should be noted, however, that IVIG treatment is limited to hypo-IgGemia and is not effective for cellular immunodeficiency. Cellular immunodeficiency can be treated with thymosin-based agents, which have the effect of regulating T-cell proliferation and differentiation. In children with adenosine deaminase (ADA) deficiency, red blood cells can be infused, as they are rich in ADA, or bovine adenosine deaminase combined with polyethylene glycol (PEG-ADA) can be used as an enzyme replacement and can be successfully treated in a small number of children with ADA deficiency. In addition, cytokines can be used to treat some primary immunodeficiency diseases, such as interleukin 2 for severe combined immunodeficiency diseases. Immune reconstitution is the implantation of normal cells or genetic fragments into the patient, which can correct the immune deficiency in a durable manner. Such approaches include hematopoietic stem cell transplantation, thymic tissue transplantation, and gene therapy. Hematopoietic stem cell transplantation, which in turn includes bone marrow stem cell transplantation, umbilical cord blood stem cell transplantation and peripheral blood stem cell transplantation, is used to treat diseases such as combined immunodeficiency and phagocytosis defects. The Shanghai Children’s Medical Center of Xinhua Hospital of Shanghai Jiaotong University School of Medicine successfully performed bone marrow stem cell transplantation on a child with hyper-IgMemia and a child with WAS syndrome in 2006, starting a precedent of using this method to treat children with primary immunodeficiency diseases in China. At present, many mutated genes of primary immunodeficiency diseases have been cloned and their mutation locations have been identified, which provides a good basis for gene therapy. In short, gene therapy is a therapeutic treatment that involves implanting a normal gene into the patient by certain means, so that it can be replicated and persist in the patient’s body for therapeutic purposes. Currently, this treatment is still in the exploration and clinical validation stage, and it will take time to be widely used as a clinical treatment. In conclusion, the treatment of primary immunodeficiency diseases is developing very rapidly and some primary immunodeficiency diseases are curable. Therefore, parents must have the confidence to lead their children to persevere with treatment and overcome the disease.