The purpose of the study was to clarify the methodological foundations of the essence of public administration bodies as subjects of administrative procedural law. The methodology of scientific work is determined by the optimal combination of general and special methods of scientific knowledge, which made it possible to form a holistic understanding of the legal form of social phenomena accompanying the development of the state. It is proved that administrative procedural law has its own system, the primary element of which is the administrative procedural norm, so that its normative impact coincides with the purpose of administrative procedural law, namely the practical implementation of administrative and legal norms in the field of public law and, by extension, public administration, ie the transformation of substantive administrative law norms at the level of practical implementation of a particular right of a person. The system of administrative procedural law, consisting of rules, institutions and administrative procedural sub-sectors, stands out. Everything leads to the conclusion that the system of administrativeprocedural law is in the formative stage and is structurally composed of administrative-procedural norms, institutions and sub-branches and is essentially related to the substantive norms of administrative law.