It is indicated that the key problem in the activity of the Constitutional Court of Ukraine is ensuring the implementation of its decisions. Without solving this issue, it is impossible to guarantee the supremacy of the Constitution, the principle of separation of powers and the existence of an independent judicial branch of government as a separate institution. Ignoring the decisions of the constitutional control body undermines the very system of checks and balances, the authority of the Basic Law and the constitutional order in the country in general. These principles underlie the implementation of decisions of constitutional courts, the purpose of which is to ensure constitutional legality. In Ukraine, the mechanism for the implementation of the decisions of the Central Committee of Ukraine has already been developed in general, but there are problems related to the non-implementation of some of its decisions for a long time. Therefore, the task of further improvement of this mechanism and its proper legislative regulation remains relevant. The authors claim that Ukraine has already developed a mechanism for implementing decisions of the Constitutional Court. However, this system is not perfect, which is evidenced by the fact of non-execution of individual court decisions. Therefore, the issue of continuing the work on improving the existing mechanism for implementing decisions of the body of constitutional jurisdiction, securing it properly at the legislative level, remains urgent. At the same time, the problem of the quality of such execution comes to the fore, for the solution of which it is necessary to develop criteria for the effectiveness of the execution of court decisions, which will allow to assess the quality of the legal acts that are introduced and the work of the responsible entities. Both outlined problems definitely need further thorough scientific research. In addition, according to the authors, it should be noted that the issues of the legal nature of the legal positions of the Constitutional Court of Ukraine and the criteria for the effective implementation of its decisions remain interacting categories and, therefore, require thorough scientific study. At the same time, clarifying the legal force of the Court’s legal positions is complicated by the lack of their legislative definition, by a certain difficulty in understanding the role and place of the body of constitutional jurisdiction in the system of state power. At the same time, the legal positions have a normative and mandatory character, reflected in the acts of the KSU. The need to ensure their immutability follows from the principles of legal certainty and stability of the Constitution. However, the possibility of revising some legal positions in connection with the change in the socio-political structure of the state is gaining relevance.