The article provides a general analysis of the legal acts regulating the activities of the UK penitentiary, the list and importance for the effective functioning of the UK penitentiary is indicated. The author performed a comparative legal analysis of the main legal acts regulating the penitentiary systems of England, Northern Ireland, Scotland and Wales. The special regulatory framework on the basis of which the penitentiary systems of England, Northern Ireland, Scotland and Wales operate is identified and clarified. The list of bodies and officials managing, supervising and controlling the activities of penal institutions in England, Northern Ireland, Scotland and Wales has been also determined.
 Considerable attention was paid to the description and comparison of the powers of the Secretary of State and the Her Majesty’s Chief Inspector of Prisons, other officials and authorities of the penitentiary systems of England, Northern Ireland, Scotland and Wales, which made it possible to distinguish the differences in the powers exercised by them in the territory of each of the described territory. The proposed article, based on the performed comparative legal analysis and the identification of common and distinctive features of the penitentiary systems of England, Northern Ireland, Scotland and Wales, indicates the ways of potential optimization of the management of the penitentiary system of Ukraine in the context of the reform of the penitentiary system of Ukraine, which has been ongoing since 2016 and continues today.
 The author proposed a comparative table in the sequence "administrative-territorial unit - bodies that manage, supervise and control the activities of penal institutions - name of the document / number of the article". Based on a comprehensive comparative analysis of the legal framework, a list of common and distinctive (special) features of the management of penitentiary systems in England, Northern Ireland, Scotland and Wales was synthesized. A whole spectrum of special, sometimes unique aspects of the functioning of the penitentiary systems of England, Northern Ireland, Scotland and Wales was singled out and compared with the peculiarities of the functioning of the penitentiary system of Ukraine.