The subject of the research is the theoretical and methodological aspects of the formation of the mechanism of socio-economic development of Ukraine. Methodology. The study used the following general scientific methods: theoretical generalization; methods of positive and normative analysis, statistical analysis. The purpose of the work is to substantiate the formation of the mechanism of socio-economic development of Ukraine. Results. The purpose of the article is the formation of the mechanism of socio-economic development of Ukraine. Analysis of the socio-economic status of households in Ukraine showed that the average monthly total income of one household in 2020 was 12248 UAH. Minor disproportions are observed because the urban household received on average 12620 UAH per month, while the rural household received 11470 UAH per month. It was determined that on average per one person in a household (hereinafter people) the equivalent aggregate income (hereinafter income) was 5832 UAH per month, in urban households – 6096 UAH, in rural households – 5286 UAH. It was proved that the level of average monthly income per person was 2.8 times higher than the established subsistence minimum (2078 UAH). It was found that the main source of income in households with one child was income from work (77%), and in households with three or more children the share of this income was 1.2 times lower. The socio-economic condition of Ukrainian households is analyzed. The structure of total resources of all households is examined The structure of total household expenditures is also analyzed. The distribution of users of Internet services by purpose is studied. The formation of the mechanism of socio-economic development of Ukraine in terms of sustainable development is carried out. It is proved that the mechanism of formation and development of socio-economic systems can be characterized as a mutually agreed system of legal and methodological support, based on the basic principles of territorial systems (sustainability, multilevel, partnership, dynamism, focus on local needs, public participation) and aimed at ensuring the welfare of the community, the well-being of residents and increasing the competitiveness of the territorial system, by developing appropriate tools.