Today, the most important factor which determines the development of the world economy is economic globalization. The article presents a scheme of the interdependence of the processes that determine competitiveness of the country in the context of globalization: CER.1 -the cause-effect relation reflecting the influence of M&A with the participation of national companies on concentration of a national economy; CER.2 -reflecting the impact of concentration of the national economy on its competitiveness; CER.3reflecting the impact of intensity of M&A with the participation of national companies on their capitalization; CER.4 -reflecting the impact of the level of national companies' capitalization on competitiveness of the country. The article puts forward and proves, based on the confirmation of the above mentioned cause-effect relations, the following hypotheses: 1. -merges and acquisitions with the participation of national companies influence concentration of a national economy which in turn determines the level of its competitiveness; 2.integration with the participation of national companies through implementation of M&A increases their market capitalization, thereby affecting the level of competitiveness of the country. For simulating, the correlation and regression modeling is used. The statistical base of the study comprises a sample of 42 countries of the world.