The article analyzes various approaches to determining the principles of administrative law, administrative procedure and disclosure of their essence. The article formulates and reveals a system of principles for monitoring state aid to economic entities in Ukraine. It has been found out that the basic principles of public administration activity in the analyzed sphere are: the rule of law, legality, transparency, equal opportunities, timeliness, objectivity, regularity, mutual cooperation, prevention, efficiency, completeness, competence (professionalism), independence, protection and storage of information, protection of competition, public interest consideration, etc. It is concluded that disclosure of the essence of the state aid principles to economic entities will give an opportunity to understand the monitoring of state aid, differentiate it from other related legal concepts, such as control and supervision, will allow to form an effective system of information support of the activities of governing bodies and to facilitate the development of legal norms, which will ensure the effectiveness of this activity.