Abstract: The subject of this study are the concepts used to regulate public relations related to the realization of ownership of goods transported across the customs border, power relations between customs authorities and persons exercising ownership of goods, as well as public relations related to the regulation of customs affairs. The authors consider in detail the established legal and scientific approaches to the definition of the basic concepts of customs law, the analysis of which reveals their essential features, essence and content. The authors study in detail such concepts as customs legal relations, customs control, customs regulation, customs business, customs administration, customs policy, customs law, customs legislation and others. Special attention in the framework of the study is paid to providing a comprehensive analysis of these concepts, taking into account the specifics of approaches to their understanding in various spheres of public relations. The authors used general scientific methods (abstraction, induction, deduction, hypothesis, analogy, synthesis, typology, classification, systematization, generalization and others) as well as special methods of scientific cognition characteristic of jurisprudence (comparative law, historical, formal law, legal hermeneutics, system-structural, legal modeling and others). The scientific novelty of the research lies in the conclusions and proposals aimed at improving the basic terminology of customs law, based on ensuring uniform approaches to the unambiguous definition of the basic concepts of customs law, which do not contradict the current legislation and are aimed at its development. The authors substantiate the critical importance of unifying the understanding of customs law terms in order to achieve a unified customs regulation, uniformity of law enforcement practice during customs control and customs operations both in the customs territory of the Eurasian Economic Union and in the Russian Federation. A special contribution of the authors is the realized attempt to integrate the approaches of the legislator, representatives of legal and economic sciences to the definition of customs law concepts as the only guarantee of effective regulation and management of public relations in the field of foreign economic activity.