Approaches to determine the economic category of "integration" are considered in the article. Author has proved that defining economic direction of development of Ukraine's economy, its gradual integration into European political, economic and legal space as a priority needs a deeper research in this direction. The aim of the article is an analysis of research of Ukrainian and foreign scientists aimed at the definition of the concept of "integration" and based on this analysis the justification of author's interpretation of this concept. The methods of historical and retrospective analysis, synthesis, induction and deduction were applied. The necessity to study the concept of "integration as a process" and "integration as a set of relations" was grounded. It is proved in the article that key conditions of integration are the level of development of countries, their resource and technological potentials; maturity grade of market relations; scopes and prospects of development of economic relationships of countries; infrastructure and socio-cultural compatibility. Based on the results of systematization and analysis of the existing concepts it was defined that the economic integration is nothing other than a union of states due to limited natural, labor and financial resources in this or the other country for creating goods that are competitive in these markets and overcoming the crisis phenomena in countries, such as the impoverishment of nations, unemployment, devaluation of national currencies that lead to social problems in those countries. The basic types of economic integration, such as the formation of the global economy principles and the preserving of economic independence of the national economy, were analyzed. It was determined that the model of European integration processes, which is defined for the economy of Ukraine, focused on the first type of economic integration, which is impossible in conditions of low level of competitiveness of Ukrainian economic entities. The conclusion about the need to revise the existing principles of economic integration due to the low level of competitiveness of the national economy was made. Further studies will be directed on the determination of the effectiveness of the processes of economic integration in Ukraine.