The work is devoted to the research of essence of constituing of social subjects of political process in modern Ukraine as to the process of their assertion and becoming in society, changes and fixing of their status which includes political subjectivation, advancement of political, economic, social, cultural requirements, and also institutional and normatively legal registration in the political system. Besides it, for more detailed consideration the social subjects of policy were specified and formulated author determinations some of them (in particular, "religious community", "ethnie", "nation", "ethnic minority", "national minority", "ethnic group", "native people", "ethno-national community"). Essence of institutionalization of social subjects of policy (constituent of their constituing) is found out also as a process of organization, equipping with modern amenities and formalization of their activity (whether separate representatives), and also relations, between them or with the state in relation to a receipt and strengthening of power, allocation of social and financial resources, maintenance and development of own identity, providing of harmonious cohabitation, within the framework of the political system. At the same time, the basic displays of institutionalization of social subjects of political process are selected and analyzed on the example of demographic, professional, religious and ethno national communities in Ukraine. It is set that politicization is the necessary condition of institutionalization subjects of political process. Except it, the basic features of their politicization are analyzed in Ukrainian society by the protracted monitoring and analysis of scientific and expert publications, materials of mass medias, and also internet resources. In particular, the features of politicization of demographic and professional communities: actualization of socio-economic questions, protest activity, high level of the personal ambitions and interests of their leaders; religious communities is chain character, external influence on them, high level of the personal ambitions and interests of their leaders, considerable role of irrational factor; ethnonational communities is chain character, considerable external influence, separative manifestation, high level of the personal ambitions and interests of their leaders.
