| Power is the important social phenomenon existing in the human society. As for the essence, power is a kind of public will and public power should maximize the public interests as its operating basic principle. However, power is easy to make people corrupt, absolute power makes people corrupt absolutely. Power's this specific property determines that if the public power can't be restricted, it will be abused or be utilized to play one's own game. So we must strengthen supervision and restriction on power. And as a kind of political ideas and model, constitutionalism is a set of systematic designs to restrain the public power initially. Restriction on the public power and constitutionalism are related to closely. Constitutionalism, as a institutional system, should give play to the leading role in restricting the public power.Learning the relationship between the restriction on the public power and constitutionalism, need to have a clear idea about the intension of the public power and constitutionalism. On the basis of the analysis of the intention of the public power and constitutionalism, this article disclosed the inherent relations between them: Constitutionalism stems from the demands of restricting the public power; restriction on the public power is the spiritual gist of constitutionalism. Historically speaking, just based on the legal control of the public power, it produced constitution and realized constitutionalism; controlling and restricting power by constitution and laws and practicing power restrains are the constitutionalist's most essential demands and principal function, which is reflected in some respects as follows: Compared with democracy, constitutionalism more stresses the restriction and prevention on the public power; the constitutional spirit of power restrains is embodied by constitution; power restrains is also the subject which is strongly displayed by constitutional systems, such as the representative system, the elective system, the decentralized and balanced system, etc.We must check and restrict power, which is mainly determined by power nature, character weakness, defects of the representative system and demands of the market economy and so on. And to restrict power effectively, system is the most essential and leading dependent strength. Restricting power by system is the basic restriction on it, which is also a major difference between rule of person and rule of law. As for the relation between system and human, Deng Xiao-ping firmly thinks that system is more important and also more dependent than human. Not that human nature is the major factor of problem determination, but that system is the key in determining the success or failure of the cause of the Party and the People. Only bringing power operation into the orbit of systematization and legalization, we can avoid and eliminate the phenomenon of power deterioration. Constitutionalism is just a kind of rule and system limiting and regulating the operation of the public power through legalized political order. Compared with such methods of power constraint as rule of law, democracy, constitutionalism is the best systematic arranges of realizing power constraint, and also the inevitable choice of systematizing the power constraint.In China, to achieve effective power restriction, we must strengthen constitutional system construction. During hundreds-of-years constitutional development, western countries have set up a set of complete power constraint mechanism. Different from the system of "separation of the three powers in western countries, supervisory system of the People's Congress is a systematical choice according to Chinese constitutional practice. In restricting power of government, we may draw lessons from the western countries' experiences of power restriction, and blaze new trails about system according to Chinese actual situations: We must further improve and perfect the supervisory system of the People's Congress on the basis of sticking to it, and enhance the supervising effect of the People's Congress, to offer better systematical circumstances for China's constitutionalism construction; must establish the perfect system of constitutional litigation and give full play to the role of restricting the public power by civil rights; must build the system of effective unconstitutional investigation and intensify the constitutional restriction on the public power. |