We are the witnesses of numerous and various changes in the world economy for a long time. Primarily, these changes are inspired by the process of globalization of the whole economy. The previously mentioned movements ( or changes) are constantly stimulating us to think and understand the problems of the global world, but first of all the phenomenon of transnational companies as an obligatory factor of today`s world. The purpose of this paper-work is to point out the main characteristics and forms of operating of transnational companies as well as their organizational structure and importance in the world economy. It is the fact that transnational companies control the significant part of the world production and trade, investment and technological flows. According to this, the aim of this paper-work is to enable easier understanding of both their positive and negative effects on the economy of the countries in transition. The aim of this work is also to present both international and political influence of transnational companies, then to come to adequate conclusions concerning both advantages and disadvantages they produce, and to point out the fact that transnational companies, by their doing, lead to making a new economic order.