The normal value of lymphocyte percentage is 20.0% to 40.0%. It is normal for children under the age of 4 to 6 to have an increased rate, but in adults, increased lymphocyte percentage is mainly due to viral infections, malignant tumors of the lymphatic system, and other causes. 1. Viral infections: such as viral colds, rubella virus, mumps, epidemic hemorrhagic fever and other viral infectious diseases. 2. Malignant tumors of lymphatic system: such as acute lymphoblastic leukemia, mature lymphoblastic leukemia, lymphoma and other malignant tumors. 3. In addition, aplastic anemia, granulocytopenia and other diseases neutropenia, resulting in increased lymphocyte ratio. Of course, only based on a test result is not able to judge or diagnose the disease, should consult the doctor in time, the doctor will be based on the specific circumstances, comprehensive analysis, clear diagnosis.