Low lymphocyte counts should be treated with the appropriate medication chosen according to the cause of the low lymphocyte count. Common causes include infections, hematologic diseases or side effects of drugs, etc. Treatment includes antiviral therapy (e.g. tenofovir), chemotherapeutic drugs (e.g. cytarabine) and so on. 1. Infection: pathogenic microorganisms infection caused by the body’s low immune function, should actively treat the original disease. For example, AIDS is caused by human immunodeficiency virus, which can be treated with tenofovir, lamivudine and other antiviral therapy. 2. Hematological diseases: including acute leukemia, aplastic anemia, etc., need to treat the cause of the disease, such as acute myeloid leukemia can use high-dose chemotherapeutic drugs such as Zoerythromycin, cytarabine, etc. Combined chemotherapy, rapid removal of leukemia cells in the body, to achieve a complete remission of hematological. 3. Side effects of drugs: the application of immunosuppressants and large amounts of glucocorticoids such as dexamethasone and cytarabine during the treatment of the disease will have an effect on the immune function, and the lymphocyte counts will gradually rise after the discontinuation of these drugs. There may be other reasons for low lymphocyte count, such as genetic factors, radiation therapy, etc. It is recommended to improve the examination in a timely manner, to clarify the cause of the disease, and then standardize the treatment under the guidance of a doctor. The above drugs should be used under the guidance of a doctor, avoid self-medication.