Since 2019, the Ministry of Health and Welfare and the National Agency for Management of Life-Sustaining Treatment has been conducting surveys of public awareness of the system for making decisions to forego life-sustaining treatment (LST). The purpose of these surveys is to ascertain public awareness of the system and to identify ways to improve it. In 2020, for the first time since the system’s implementation, a survey was conducted on those who used either Registry Agencies for Advance Directives or medical institutions with ethics committees established according to the system for making decisions to forego LST. The mobile user survey of 1,426 people was conducted from November 2 to 23, 2020. In this article, we derive five policy suggestions based on the survey results: (1) A public education program on the end of life should be developed; (2) Systematic consumer-tailored public relations strategies should be implemented to better promote the system. (3) Registry agencies and medical institutions should be encouraged to increase user accessibility to the system; (4) Counseling aids, such as explanatory materials and various information delivery tools, should be provided for better decision-making on LST; and (5) A communication channel should be opened with the public.