The article examines the position in the competitive market of the European Union and the Eurasian Economic Union in the field of Antimonopoly regulation of relations and their impact on market participants. For the analysis we take the normative and legal base, formed by the European Commission and the European Court of justice and the Eurasian economic Commission and the Court of the Eurasian economic community. Using the results of their research, the authors give suggestions on how you can harmonize and improve the relations of participants of the market in question Antimonopoly policy of the EU and the Eurasian Economic Union.