Memory will decline moderately with age, but it will not affect comprehension and calculation ability is a physiological phenomenon and does not require special treatment. If there is a significant decline in memory within a short period of time, you should be highly alert to common diseases such as Alzheimer’s disease and vascular dementia. The cause of Alzheimer’s disease is unknown. Patients often have a family history of memory loss, personality changes, brain atrophy and ventricular enlargement on cranial imaging, and severe symptoms that can affect the patient’s daily life. There is no specific treatment for Alzheimer’s disease. Oral treatment with drugs such as oracetam, amantadine and donepezil is available. Vascular dementia is mostly seen in brain infarction and brain hemorrhage within six months after the onset of memory loss. Patients will also suffer from limb weakness, sensory impairment, dizziness, and choking on water. Effective secondary prevention of vascular dementia should be carried out to avoid further aggravation of cerebrovascular disease. Drugs to improve memory include amantadine and donepezil.