The effects that previous foreign direct investments have had and have on the competitiveness of the Republic of Croatia have been analyzed in this diploma thesis, over a time series of 21 years. The issue of the structure and volume of direct investment is discussed from a theoretical and practical point of view, the experiences of developed and developing economies, and the advantages and disadvantages that arise from them. Most often, advocates of higher FDI inflows argue their views with GDP growth, higher employment, price stability, increased exports of goods and services, higher competitiveness index and generally better living standards of Croatian citizens. Opponents of the policy of indiscriminate attraction of foreign direct investment explain their views by bad experiences from the time of transformation and privatization of Croatian companies, concern for the preservation of space, natural environment and commitment to sustainable development. In addition, all the complexity of the real analysis of the effects of FDI on a country is expressed in times of disruption of global capital flows caused by major (GFK or COVID 19) or minor local crises, when all economic activity slows down or moves to safer areas. The paper sought to point out the trends arising from these data, taking into account the data of UNCTAD, HNB and DZS, as an undoubtedly strong argument for the claim that increased inflows of foreign direct investment have a positive impact on the competitiveness of the Republic of Croatia.