A high CV of red blood cell distribution width generally means that the patient’s red blood cell volume is more variable. It means that the patient may have anemia, myelodysplastic syndrome and other problems in the body, and the specific causes have to be analyzed comprehensively. 1. Anemia mainly includes iron deficiency anemia, aplastic anemia, megaloblastic anemia, etc. Some of the red blood cells of these patients will have increased volume, resulting in a high coefficient of variation of red blood cell distribution width. 2. Patients with myelodysplastic syndromes have abnormal hematopoietic stem cells, and the volume of their red blood cells may be large or small, resulting in a high coefficient of variation of red blood cell distribution width. If the CV of erythrocyte distribution width is high, the patient should consult the doctor in time, and under the doctor’s guidance, carry out further examination to clarify the condition and then carry out standardized treatment.