There are physiological and pathological reasons for high white blood cells. Physiological increases are seen in strenuous activities, etc. Pathological increases are mainly due to bacterial infections, and can also be seen in other diseases, such as leukemia. 1. Physiological increase Physiological increase of leukocytes can be seen in strenuous exercise, physical activity, emotional stress, full meal, end of pregnancy, labor and delivery, etc. In these cases, leukocytes increase. In these cases, the increase in white blood cells is temporary and can be quickly recovered after removing the influencing factors. 2. Pathological increase Pathological increase of white blood cells can be seen in infectious diseases, especially bacterial infections. Secondly, it can also be seen in hematologic diseases, such as leukemia. Pathological increase can also be seen in acute hemorrhage, acute poisoning, severe tissue injury, large burns, malignant tumors and so on. If there is a leukocyte increase, further examination should be carried out to clarify the cause under the guidance of the doctor, and if it is a pathologic increase, targeted treatment should be taken in a timely manner to avoid delaying the condition.