Currently with the becoming age society it joins in with absolute increase of the elderly population and the dementia is increasing, also the serious problem is increasing. Consequently the integrated research for the support system of the family, preparation of the individual, role of the community and the quality of life improvement of the elderly which connection makes welfare policy of the elderly in the nation system is necessary. The purpose of this study is to investigates the quality of life-dementia, the data it leads and the population social factor of the dementia with life of the dementia probably has a relationship, it analyzes. And it presents the fundamental data it will be able to compose the policy dimensions which are various and practice domains rationally. It will reach and to lead it gropes it does the quality improvement and a problem solving plan of life of the dementia. Research task of this paper is as following : 1) Is the present condition of quality of life-dementia what? 2) Is the care environment of the dementia how? 3) With quality of life-dementia is the population social factor of the dementia who is relation what?