Whether a low lymphocyte percentage is important or not depends on the specific situation. Lymphocytes are a type of white blood cells that play a major role in the body in fighting infections, tumors, and other immune functions. Lymphocyte percentage refers to the proportion of lymphocytes in white blood cells. Under normal circumstances, the lymphocyte percentage is 20% to 40%. Low percentage includes relative low percentage caused by elevated neutrophils and absolute low percentage caused by absolute decrease of lymphocytes. 1. Relatively low lymphocytes caused by neutrophilia are mainly seen in various bacterial infections, severe tissue injury, etc. If the condition is serious, it is necessary to be vigilant and give anti-infective and other targeted treatments in time, such as levofloxacin; 2. Absolute low lymphocyte percentage is mainly seen in aplastic anemia, adrenocorticotropic hormone use, immunodeficiency diseases and so on. If the lymphocyte percentage is found to be low, it should be combined with other relevant laboratory indicators and one’s own symptoms, and one should go to the hospital in time and receive treatment under the guidance of the physician.