The jurisdiction of the Constitutional Court is Enumeration. That is to say the jurisdiction of the Constitutional Court must be prescribed only in the Constitution and can not be interpreted in any extension beyond the spirit of the Constitution. This Thesis studies on the concepts and essential theories which are the foundation of the jurisdiction of the Constitutional Court under the Constitution B.E. 2540, the Constitution that established the Constitutional Court in Thailand for the first time. Nevertheless, after this Constitution has come into force, there are many problems occur concerning the jurisdiction of the Constitutional Court e.g. lack of organization to give opinion on the interpretation of the Constitution, the laws resulting the expansion of jurisdiction of the Constitutional Court, problems of the Judicial Review on the constitutionality of the Act and the subordinate legislation, problems of the Judicial Review on the exercise of power of the Constitutional Organ and problems of the legal control of the appointee recruitment under Constitutional Organ. The Constitution B.E. 2550 has resolved only some problems. The author, thus, proposes the resolutions by authorizing the Supreme Administrative Court to have the jurisdiction review on the exercise of power of the Constitutional Organ and the appointee recruitment under Constitutional Organ, classifying the provision of the Constitutional Organ and dismissing the Prosecution Organization and the National Economic and Social Advisory Council from being the Constitutional Organ, and adding the provision allowing the Parliament to enact the expansion of the jurisdiction of the Constitutional Court under the condition that such expanded jurisdiction must be in relation to the Jurisdiction set out under the Constitution.
