The article deals with fiscal policy in the decentralized space of the financial system of Ukraine. The methodology of complex, systematic assessment of fiscal policy in the decentralized space of the financial system of the state is grounded. It is proved that effective methodological approach to assessing fiscal policy in the decentralized space of the financial system of the state is a vector auto regression (VAR), which provides dynamic correlation of time series with simultaneous determination of each exogenous and endogenous variable in the system, in case of fiscal impulses (shocks) in economy. The production-institutional function is used which, when adapting to the relationship between GDP and tax burden with specific statist...