Anemia can be divided into many types according to etiology and morphology, and each has different pathological mechanisms. In general, there are three categories: hematopoiesis (iron deficiency anemia, aplastic anemia, etc.), excessive destruction of red blood cells (various hemolytic anemias), and acute and chronic hemorrhagic anemia. All types of anemia can produce some common clinical symptoms due to the reduced oxygen-carrying capacity of the blood and insufficient blood supply to brain cells, resulting in ischemia and hypoxia of brain cells. However, due to the nature of the primary disease, the speed of onset and the age of the patient, the clinical manifestations are also different. However, the mental disorders associated with various types of anemia are all mental disorders that affect brain function.