Procedural-institutional forming of Ukrainian state was a complex process of state-administrative apparatus forming on central and local levels with the simultaneous development of relation’s regulation mechanisms both between the subjects of power and between its bearers and society. The organizational core of the state institute was formed on the legal principles of the political organization of the Cossack society, which also became the origin of the new Ukrainian political elite. The Ukrainian state was ruled through the interaction of two institutions — the Supreme Council and the Hetman, the relationship between which often influenced the effectiveness of the whole administrative vertical. The lower levels of the structural hierarchy consisted of the central and local authorities — the institutions of general, regimental and hundred foremen, bailiffs and atamans in the countryside, General Chancellery of the army, General Military Court, regimental and hundred managerial and judicial structures, local town councils and boards of shopkeepers, kopni courts, etc., through which the power monopoly to regulate public life was established. The electoral system was used for the formation of the power structures, although it was also common practice for some positions to be held by appointment. The Ukrainian elite of Hetmanshchyna in the late 17th-early 18th century displayed a tendency towards the European model of monarchism in its state structure. However, due to constant interference of Russian authorities in Ukrainian domestic political affairs, republican institutions remained the only ones through which the ideas of Ukrainian political subjectivity could be realized. The assertion of the Cossack senior officers’ full ownership of their estates determined the evolution of the republican form of government into an aristocratic republic. The comprehension of struggle between hetmans and general starshinas and development of political system of Zaporozhian Host reflected on the formation of aristocratic-democratic current in Ukrainian political thought.