Chronic lymphatic leukemia in the elderly may be caused by genetic or biochemical factors, ionizing radiation and other factors. 1. Heredity: the prevalence of chronic lymphatic leukemia in the immediate family members of patients with chronic lymphatic leukemia is about three times higher than that of the general population, which indicates that hereditary factors play a certain role in the development of chronic lymphatic leukemia and may be the cause of chronic lymphatic leukemia in the elderly. 2. Biochemical factors: taking chemotherapeutic drugs or long-term exposure to chemicals may be the cause of chronic lymphatic leukemia in the elderly. 3. Ionizing radiation: prolonged exposure to ionizing magnetic fields will cause abnormalities in the body cells, which in turn will cause abnormalities in the hematopoietic stem cells and may be the cause of chronic lymphatic leukemia in the elderly. The causes of chronic lymphatic leukemia in the elderly are varied, and it is recommended that patients under the guidance of the doctor to carry out examinations to clarify the cause of the disease and actively treat it.