The rising population of elderly worldwide has led to an increasing number of people with dementia. Managing and providing quality care for people with dementia has thus become a priority public health issue in developed countries. Dementia is a gradually degenerative disease. In the absence of a cure, improving, maintaining or maximizing quality of life is becoming the primary goal of nursing care for patients with this disease. Quality of life is an important outcome index of medical care and can be a criterion for making health economics decisions. The fact that dementia is a disease that presents steadily declining cognitive function has led to numerous challenges and debates regarding the optimal concepts and methodologies to be used to measure quality of life in those with dementia. This paper reviews relevant debates on these issues and makes suggestions that may serve as guides to monitoring/studying quality of life in dementia patients.