[European Congresses and Constitutional Review on Laws] This research aims to minimize unconstitutional laws and search for the improvement of system in legislative process by surveying the European cases of constitutional review system. The constitutional review on the laws has the function to protect the basic human rights of the people especially from the legislative infringement. Korean constitutional review system has more than 20 year history. Our congress has been trying to reform the unconstitutional laws after constitutional court＇s decisions. However we tried to find out the advanced system to minimize unconstitutionality in the laws from the experience of the European nations such as France， Spain， Germany and Austria. Before we went to Europe， we had seminars on the constitutional review system of the european nations with eminent scholars. In Europe we interviewed the experts in charge in the Congress and Constitutional Courts. All the nations have both the abstract and concrete constitutional review system. When we discuss to introduce an abstract constitutional review system， we should consider the experience of the european nations. The European experience shows that the role of it is to protect the minority， however， the case is rare， and the relation between the constitutional court and congress has been stabilized. These conditions are the key points for the successful system. We thought that abstract review on the treaty is needed in that the treaty has influences over the daily lives increasingly. However， the abstract review on law system in under the reform of the constitutional law. So the practical alternative would be the arrangement of the constitutional legislative review in congress. If we intensify the legislative process to refer a law to the constitution， we may not need the abstract review system of constitutional court. Last， we suggest that the congress should submit a legislative intension opinion in the constitutional review process in the constitutional court.