EBV NA refers to nuclear antigen, EBV NA antibody IgG positive, suggesting that the patient has been infected with EBV in the past, when infected with EBV the body will produce IgG antibody. There are three types of EBV IgG antibodies: EA-IgG, VCA-IgG, and NA-IgG, which is one of the important indicators to determine whether a patient is suffering from infectious mononucleosis, nasopharyngeal carcinoma, and other related diseases. And positive EBV NA-IgG antibody will appear late in the recovery period of the disease, which is of guiding significance for the diagnosis and identification of the disease. Patients are advised to have regular medical checkups, and if they feel unwell, they should seek medical examination and treatment in time.