B a c k g r o u n d . Strengthening the financial basis of local self-government takes on archival importance, considering the economic circumstances of the wartime and post-war reconstruction of the territories of Ukraine. In this regard there is a need to improve the local finance management system and develop its institutional support in conditions of financial decentralization. Theoretical and practical aspects of management in the field of local finances, inter-budgetary relations, financial relations of local self-government bodies in the context of decentralization are considered in the works of domestic scientists: V. Bodrov, V. Vakulenko, I. Volokhova, N. Honcharuk, V. Gornyk, A. Degtyar. The strengthening of the financial basis of local selfgovernment in the process of the post-war recovery of the economy of Ukraine is studied in the works of Z. Varnalij, I. Vertsiuk, Ya. Zhalilo, M. Kosheliuk, I. Ozymok, O. Sokolova, U. Thomann and others. Implementation of financial decentralization, management of local finances is considered by such foreign scientists as: J. Buchanan, A. Wagner, R. Musgrave, W. Oates, P. Samuelson, J. Stiglitz, H. Zimmerman, F. Fukuyama, J. Schumpeter and others. It remains expedient to search for institutional mechanisms for further reforming the financial relations of local self-government bodies, models for managing inter-budgetary relations, sources of financing local budget expenditures, and expanding public control mechanisms in the process of managing local finances under conditions of decentralization. The purpose of the article is the scientific and theoretical justification of the institutional transformations of the local finance system of Ukraine and the development of practical recommendations regarding the mechanisms of its development in the context of the decentralization of state administration. The tasks of the article are to consider the existing problems and outline the prospects for ensuring the processes of financial decentralization, to propose mechanisms for the necessary institutional transformations in the system of local finance of Ukraine and tools for their implementation. M e t h o d s . The article was carried out with the help of modern theoretical and cognitive methods, the dialectics of the processes of public administration and local self-government in the conditions of financial decentralization and reforming of local finances. Methods of system analysis, synthesis and comparisons, historical, logical, deductive methods and modeling were also used. The research used the theory of public choice, public goods and the structural-functional approach to improve the management of budget funds in conditions of decentralization. R e s u l t s . It is claimed that the pre-war experience of active implementation of the decentralization reform in Ukraine gave positive results, from which it is necessary to move on, and further develop and improve this vector. It was determined that institutional transformations should take place within the framework of financial support system structural elements of local self-government – budgets of different levels. The mechanisms of the necessary institutional transformations in the local finances system in Ukraine and the tools for their implementation are proposed. In particular, such a method of improving the local finances system as budget cooperation is proposed. The Law of Ukraine norms "On Cooperation of Territorial Communities" have been analyzed and proposals have been made to expand the regulatory influence of the specified law regarding budget cooperation procedures. Attention was focused on the importance of training modern personnel of local self-government bodies that implement policies in the sphere of budget, finance and prices. The importance of the development of the institution of civil society is also emphasized. Emphasis is placed on the expansion of models and forms of self-organization bodies cooperation of the population in the processes of control and supervision of the local self-government bodies activities in the local finances field in Ukraine. C o n c l u s i o n s . Therefore, the goal of institutional transformations of the local finance system of Ukraine in the context of decentralization is to significantly expand the capabilities of local self-government bodies to independently manage all socio-economic processes at the level of territorial communities and to establish connections between regions, the symbiosis of which can bring the desired effect for the economy of the entire country. Such changes should be synchronized with the changes envisaged by the plan for Ukraine to acquire the status of an EU member state. Our proposals are designed to improve the quality of local self-government and encourage further scientific research in the field of local finance management in Ukraine.