Nowadays discussion on human rights are focused on the infringement of human rights of the weak by the socially strong persons and social discrimination. Also, the trend of understanding the human rights as the self-realization is getting stronger. Therefore, the concept of the self-determination right and the self-expression right has come to bear a very significant meaning, and in fact it is keenly needed for the disabled, females, foreign immigrants, HIV-positive persons, etc. to overcome social discrimination and human rights infringement and to promote self-realization while making themselves stay in a clear position. Therefore, new legal structures have emerged in various types according to the new ways of thinking about the human rights in such circumstances, and thus it may be said that the relationship between the self-determination right and the legal capacity system of the mentally disabled persons belongs to a very significant subject. Particularly in such a system of making massive production of the uniform and legally incompetent persons like ours, it becomes inevitable to have a large number of subjects that are to be discussed more in the systematic and ideological dimension. Therefore, as a premise for understanding the realities of the Korean system for the legally incompetent persons, the author has conducted a study specifically on the Japanese adult guardship system which makes it possible to take flexible as well as elastic measures in compliance with the degree of everyone's diversified power of judgment and necessity for protection in order to make the ideology of "respect for sekf-decision" harmonized with the ideology of "protection of oneself" among examples of legislation in foreign countries, and has prepared this writing so that a constant direction may be presented in order to realize the constitutional ideology of human dignity when our civil law will be amended in the future. In other words, as the system for the legally incompetent persons is based upon the modern thought of the 19th century, it has inherently apprehensions of consequently being contrary to the constitutional ideology of a welfare state, so to speak, unconstitutional traits without being conforming to modern legal sense and it has the problem of being a system with too much emphasis on property management rather than on inheritor protection and physical custody. Therefore, it is emphasized that the enactment of the adult guardship law of a new type in consideration of the protection of the disabled of socially weak persons together with completing throughly of the respect for self-determination right, ideology of generalization and respect for survival ability as seen to be the most important ideologies in the modern society while recognizing the problems of the current-effective system for the legally incompetent persons by changing the basic ideological foundation which is existing in the system for the legally incompetent persons, and through doing this, a systematic foundation to protect the disabled of the insufficient ability of judgment is to be set up, and thus ① it is to become an easy system for people's use in order to promote social welfare fully for the intellectually or mentally disabled persons, ② a system conforming to the Korean economic, cultural and social environment is to be induced through a comparative review while recognizing the presence of the problem of low-level utilization because the currently effective system for the disabled persons is a system that is equally depriving the legal capacity, ③ efforts will have to be made to improve the method of public notices, etc. because, notwithstanding the concerned person, all the family members will not like the current system where all sentenced facts are being publically noticed by making them recorded in the family register.