Article 41 of the Constitution of Japan stipulates the Diet shall be the highest organn of Japan stipulates the Diet shall be the highest organ of state power, and shall be the sole law-making organ of the state. And article 95 thereof states that the special law, applicable only to noe local public entity, cannot be enacted by the Diet without the consent of the majority of the voters of the local public entity concerned, obtatained in accordance with the law. This paper tries to arrange the special law theories and to outline the constitutional structure of the decentralization. Article 41 includes two principles. The first one is the Diet makes general law. In actuality, the Diet has never made local law according ot article 95 since the 1950s. However the legislature has made various special laws, that is to say, the Diet has made the general laws to which all persons and all things concerned applies, and the Government has made the special orders to appoint a specific prefecture, city or town. This form the Diet and the Government take frequently has not be always upholded by article 41. The second principle is only the Diet legislates form beginning to end. So not legally but virtually, many people are involved in the process of making the law. For instance, recently governors and their associations are demanding regular conferences between central and local governments. These meetings must be justified by any constitutional provision. Article 95 may be suitable for that, because it prevents the local autonomy form being violated. It also protects the equality of local governments, adopts partially the direct democracy, and accepts the unique structure of a certain local governments. In addition to the permition of making local law, article 95 can give a reason for the conferences. In the local reform of 2000, drastic revision of the local self-government Act was proposed. Since then, several ways and goals promoting regional decentralization, such as the principle of subsidiarity in the EU and the Home Rule Charter in the US, have been precisely studied. But according to the present Constitution, the Diet is capable of making local law with the consent of local citizens, so we should make more effective use of the constitutional special law, taking the rule of law into consideration.