Leukocyte 0.2 should mean that the total number of white blood cells is 0.2×10⁹/L, which is a severe low and is very serious. The normal range of total leukocyte count is (4 to 10) × 10⁹/L, and below 4 × 10⁹/L it can be called leukopenia. A leukocyte level of 0.2 x 10⁹/L is already severely below the normal range and should alert to the possibility of disease. Clinically, a decrease in the total number of leukocytes can be seen in diseases such as gram-negative bacillus or viral infections, aplastic anemia, non-leukocyte leukemia, megaloblastic anemia, and hypersplenism. Since this indicator is severely low, it requires a high degree of vigilance, regardless of the disease that caused it. However, in order to clarify the cause of low total white blood cell count, it is necessary to carry out examinations under the guidance of specialized doctors according to the specific clinical manifestations of patients. To summarize, a total white blood cell count of 0.2×10⁹/L suggests that the total white blood cell count is seriously reduced.