Legitimizing of political system makes up object of many scientific discussions and produces controversies. Matters relating to legitimizing are mainly considered in formulations in comparison with the national state what leads to conclusions about the deficit democracy in political system of the European Union. The present article proposes the glance on legitimizing through the prism of the constructivist approach with use of three attributes: identity, representation and recognition. The author characterizes their proprieties and possibility which can be used over the above mentioned problem. He underlines multi identities nature of the European society, the possibility of the expression of the recognition for the political system. This phenomenon can be expressed through the channels of civil participation in society functioning and can be verified in the investigations over legitimizes the models of the citizens representation in the system. Checking their applicability in practice of the European Union’s political system according to the author can contribute to undermine or even overthrow of thesis relating to the legitimacy deficit of the European Union’s political system.