The article discusses the state of development of the Korostyshiv city amalgamated territorial community in conditions of decentralization of authority. The main directions of reforming the system of local government are proposed and analyzed on the example of Korostyshiv ATC. It is concluded that the process of decentralization requires the complex work of competent persons and understanding of the local community of their capabilities. The first results of the socio-economic development of the Korostyshiv city amalgamated territorial community after the reform of the decentralization of the authority are analyzed. The main problems, goals, directions, tasks and measures aimed at achieving the development of ATC are identified. The directions of improving the functioning of the Korostyshiv city amalgamated territorial community in the context of the decentralization of the authority at the present stage of development are proposed. The importance of the implementation of the reform of decentralization of the authority in the development of the Korostyshiv ATC is proved and the advantages of decentralized management are determined. The issues of organization and functioning the local governments and local state administrations, their interaction and the problem of separation of governments are considered. The main elements that influence the development of local government are highlighted. It is established that the amalgamated territorial communities, which are formed on a voluntary basis according to a legislatively defined procedure and independently, at their own expense, will decide the issues of local importance, should form the basis of a new system of local self-government in Ukraine. It is definitely that the main goal of the development of the Korostishiv city amalgamated territorial community is to improve the quality of the population life through the implementation of a strategic course towards achieving economic and social self-sufficiency. It is concluded that the process of decentralization requires the complex work of competent persons and understanding of the local community of their capabilities.