The large number of regional trade agreements notified to the World Trade Organization (WTO) significantly influenced the flow of world trade. By April 2014 there had been notified 583 regional trade agreements to the WTO, of which only 379 are in force. The objective of this paper is to highlight the importance of regional trade agreements in world trade, especially the importance of establishing a regional competition policy in these agreements. The research methodology used is the analysis of legislation governing preferential trade agreements at the level of WTO, the collection and interpretation of statistical data provided by the WTO Secretariat, the case study, namely the study of literature. The paper is structured in three parts. The first part of the paper examines the basic laws based on which regional trade agreements are notified to the WTO and the evolution of these agreements in the period 1958-2013. The second part of the paper is devoted to the analysis of competition policy in regional trade agreements. In this part of the paper, to highlight the patterns of competition policy adopted under these agreements was analyzed by three case studies of competition policy in the EU, ASEAN and NAFTA. The three case studies have revealed that the three preferential trade agreements present regional competition policies with varying degrees of integration. The most complex form of competition policy is found in the European Union, because we are talking about a centralized model of competition policy. ASEAN presents a partially decentralized model, while NAFTA scrolls with a decentralized model of competition policy. The last part of the paper presents the characteristics of the four models of competition policy identified in the preferential trade agreements in force. It should be emphasized that if the initial preferential trade agreements have not put a great emphasis on the rules of competition policy, practice has shown the importance of competition policy at the regional level and there is now considerable progress in this regard.