Based on the basic theory of constitutional law，this article holds that any normative document adopted by any organ holding public power in accordance with the Constitution or laws and applicable to un-specific members of the general public should have legal effect and be able to regulate the behavior of all members of the general public within the scope of specific administrative areas. However，all public authorities enjoying the power of adopting normative documents must exercise such power in accordance with the Constitution and laws and on the bases of constitutionality and legality. From the jurisprudential point of view，there are mainly two methods of ensuring the constitutionality and legality of normative documents：legislative supervision and legislative control. The former is exercised on the basis legislative functions and powers provided by the Constitution and laws for the purpose of ensuring the effective exercise such functions and powers whereas the latter is the review，on the basis of the competence provided for in the Constitution and laws，by public authorities of the constitutionality and legality of the normative documents adopted by other public authorities，for the purpose of ensuring the unity of the legal system.