The scientific interest of the development of the theory and practice of cooperation of Central European countries of the Visegrád Group in the context of modern European integration processes is important for developing and implementing the strategy of foreign and domestic policy in European countries and Ukraine at the modern stage. At the beginning of the XXI century, under the changes in the geopolitical situation on the European continent, the countries of Central Europe (full members of the European Union) build a new operating system of international relations and accordingly continue to delegate some of their powers to suprastate institutions of the EU. The purpose of this scientific study is to determine paradigmatic aspects of European integration processes, modern threats arising in the EU, prospects for the interaction of EU countries, and to form a new format of cooperation of Ukraine and countries of the Visegrád Group. The aim of the creation of the alliance of the Visegrád Group (1991) was the desire to contribute to the construction of European security architecture and economic cooperation through the effective cooperation within European institutions. The whole activity of the Visegrád Group is aimed at strengthening stability in the Central European region. Risks in the economic sphere and strengthening of Euroscepticism are considered traditional for the EU functioning. In view of signing the Rome Declaration in 2017, the EU threats and challenges for the short-term (2018–2020) include: hybrid consequences of the aggression of the Russian Federation in Ukraine, European migrant crisis, a series of terrorist acts in European cities, unpredictable policy of the newly elected US president D. Trump in relation to the European security system, strengthening the position of far-left and far-right political forces in European states, Brexit and its consequences, in particular, risk of domino effect in other member countries of the Union. Therefore, we consider it appropriate to carry out system analysis of key relevant challenges and threats to the EU for 2018–2020 and to consider interconditionality and interdependence of problems that may affect the EU future. Given the defined trends, development and economic stability of each state are strategically important, however, special attention in this context should be paid to the analysis of the development of large countries of the European Union, such as Poland, Czech Republic, Slovakia, and Hungary. V4 countries are characterized by sustainable economic growth. If to analyse the Visegrád Four as a single national state, then the Visegrád Group is the fifth largest economy in Europe and the 12th in the world. The authors consider it too simplistic to define the essence of the Visegrád alliance only as a consolidation of the efforts of Central European countries for the sake of “returning to Europe” through Euro-Atlantic integration. In the modern dimension of events, the interaction format V4 + Ukraine is much more complex and more promising than it appears. Since joining NATO and the European Union in 1999 and 2004 by the Visegrád Group (i.e. Central European countries) geopolitically changes the status of the Central European Region, transforms bilateral and multilateral relations of Central European countries – full members of the EU with Ukraine. Moreover, this changes the system of relations within the Visegrád Four, as well as with other member states of the European Union.