Dementia is a common and frequently occurring disease in the elderly. It is the main cause of disability and death among the elderly， thus making it urgent to prevent and control dementia. Heart rate variability （HRV）， or changes in the heart rate， is an important and novel tool for assessing cardiac autonomic function. HRV has been widely used in the prognosis prediction and evaluation of clinical cardiovascular diseases due to its sensitivity， intuitiveness， and convenience. Dementia and HRV are closely related. HRV occurs in different types of dementia to some degree， and HRV may affect the development and progression of cognitive impairment through various mechanisms. This article summarizes the relationship between different types of dementia and HRV in order to evaluate HRV in patients from the perspective of prevention， reduce the risk of developing cognitive impairment， and provide a basis for more accurate diagnosis and multi-target prevention and treatment of the disease in clinical practice. ［Journal of International Neurology and Neurosurgery, 2023, 50(4): 80-84］