A persistent peripheral blood leukocyte count below 4×109/L is called leukopenia. An absolute neutrophil count of less than 0.5×109/L is called granulocyte deficiency. This group is clinically characterized by susceptibility to infections, especially in patients with granulocyte deficiency, who are highly susceptible to serious and uncontrollable infections. In patients with leukopenia, prevention of infections is of utmost importance. How can self-protection be carried out? 1, should be appropriate to strengthen exercise, appropriate walking, jogging, playing tai chi and other outdoor activities can improve the body’s own immunity. However, it is necessary to avoid heavy physical activity and overexertion, excessive exercise is counterproductive. 2, seasonal climate change, should pay attention to timely increase and decrease clothing, cold and warm. 3, pay attention to indoor air circulation, avoid to large supermarkets and other air circulation environment. 4.Patients with significantly reduced leukocytes, especially granulocyte deficiency, should wear a mask to prevent respiratory infections; pay attention to the timely use of salt water or chlorhexidine mouthwash after meals and after eating; pay attention to keep the bowels open, ensure perianal cleanliness, and use 1:5000 potassium permanganate solution to prevent perianal infections as appropriate. 5, avoid using drugs that may affect hematopoiesis, many antipyretics, painkillers, may affect the hematopoietic function, the above drugs should be used after consulting a doctor, not blindly take. 6, pay attention to self-physiological state monitoring, once the fever, cough, diarrhea, swollen gums, perianal pain and other discomfort, promptly go to the hospital for timely treatment.