The fiscal system and fiscal policy represent important features of the national sovereignty of a country and an integral part of overall economicy policy. The EU member states have built their own tax systems with the aim of collecting public revenues to cover public expenditures, but also correcting the adverse effects of market. The request for tax harmonization is result of the need to coordinate tax systems of EU member states to ensure the internal market through the free movement of production factors and improvement economic development. In addition to the trend of fiscal harmonization it's appears fiscal competition, which can be seen as a lack of cooperation between different tax jurisdictions of countries in the struggle to attracting foreign capital. The subject of paper includes process of fiscal integration within EU through the harmonization of their tax rates and bases, as well as the oncoming of tax rules and policies at the EU level. The aim of this paper is pay attention to the current problems of the fiscal harmonization and competition within EU, as well as the various arguments for and against one or the other approach.