As a result of administrative-territorial reform and processes of financial decentralization, the natural process of creating of amalgamated territorial communities (ATCs) became a regular one. The communities, based on the development of their own strategic and program documents, identified the main directions of their development, outlined the tasks and prospects for achieving of the highest quality of life of citizens in their own territories. However, in order to assess the success of the tasks set for the implementation of the strategy for the development of ATCs, it is necessary to monitor the socioeconomic development of communities. Monitoring is a qualitative instrument for managing the development of the territory. The article deals with the organizational and legal mechanism of forming a system of strategic and planning documents for the socio-economic development of amalgamated territorial communities (ATCs). In particular, the article examines the formation of a monitoring system as one of the key aspects of the organizational and economic mechanism for managing of socio-economic development of the community. It is established that in strategies and plans of development of different ATCs there is a considerable variation of indicators of socio-economic development. In this regard, it is impossible to monitor the comparative dynamics and to monitor and evaluate the socio-economic development of all ATCs on a nationwide scale. It is established that at present there is no complete method of monitoring and evaluating the socio-economic development of the amalgamated territorial communities. In this regard, in order to carry out a comparative analysis and assessment of the socio-economic development of ATCs, we should use all possibilities of consolidation of statistics on ATCs. In particular, from the analytical parts of the Strategies (plans) of the ATCs development it can be concluded that there is a statistical data on the dynamics and features of socio-economic development of ATCs, including the state of the demographic and labor resources of the ATCs, the use of natural, resource, production, technical potential, development of small and medium enterprises, employment, satisfaction of population with goods and services, access of business entities to loans and investments, environmental situation of the ATCs. The obtained work can become the basis for developing a more complete system of indicators for monitoring the socio-economic development of ATCs in Ukraine. The article proposes, in the direction of developing of a system for monitoring the socio-economic development of the amalgamated territorial communities, to increase the use of indicators in the Monitoring: macroeconomic efficiency, indicators of inclusive economic development, indicators of dynamics of quantitative and qualitative composition of the population, etc.