The normal range of spherical erythrocytes in the blood is 2.5% to 3.0%. 4% of spherical erythrocytes is considered to be increased spherical erythrocytes, which is mainly related to genetics and gene mutation, and autoimmune hemolytic anemia and other diseases can also cause secondary spherical erythrocyte increase. 1. Genetic or gene mutation: genetic or gene mutation leads to abnormal erythrocyte membrane protein gene, defective erythrocyte membrane skeleton protein, cell surface area is reduced, the cells undergo a spherical change, and more spherical erythrocytes can be seen in the blood. The deformability and flexibility of spherical erythrocytes are lower than normal erythrocytes, and they are easily destroyed when passing through the spleen, which makes them prone to hemolytic anemia. 2. Autoimmune hemolytic anemia: autoimmune hemolytic anemia can also cause red blood cell membrane abnormality, so that the red blood cells become spherical, some spherical red blood cells can be seen in the blood, and the phenomenon of spherical red blood cells in the blood. There are 4% of spherical red blood cells in the blood should go to the hospital in time, complete the examination, clarify the cause of the disease and then follow the doctor’s instructions to receive targeted treatment.