The article examines the role of the budget component of Ukraine’s fiscal policy in macroeconomic growth. The directions of increase of economic growth under the influence of financial decentralization are offered. The expediency of using multifactor economic and mathematical modelling in the study of the dynamics of the national accounts of Ukraine under the influence of indicators of the budget component of fiscal policy is substantiated. The purpose of this study is to investigate the dynamics of national accounts under the influence of the budget component of fiscal policy in the context of financial decentralization. A number of methods have been widely used in the study, including economic and mathematical modelling, correlation-regression analysis, factor analysis, and so on. These methods will underpin the development of strategic prospects for economic growth of the Ukrainian economy under conditions of financial decentralization. It is substantiated that an increase in the share of local budget expenditures in consolidated budget expenditures and a decrease in the share of state budget expenditures in GDP lead to an increase in the physical volume index of GDP and an increase in GDP in actual prices. It is also proven that the share of local budget expenditures in consolidated budget expenditures has an immediate direct impact on the GDP physical volume index. Another significant factor of direct influence on the GDP physical volume index is identified – the share of capital expenditures (development expenditures) in local budgets, as one of the indicators of financial decentralization efficiency. It is substantiated that the share of state budget expenditures in consolidated budget expenditures is a factor of inverse effect on GDP (in actual prices), and the share of capital expenditures is a factor of direct influence. It is proved that financial decentralization in Ukraine is an important factor of economic growth of the Ukrainian economy, as the increase of the share of local budget expenditures in the consolidated budget expenditures and the reduction of the share of state budget expenditures in GDP lead to an increase in the GDP physical volume index and an increase in actual GDP.