This paper aims to analyze an interpretive activity of international organizations as a means to solve the problem of paramount importance for ensuring updating of international law rules and the whole mechanism of international law action in the process of rules implementation. The methodology is based on a comprehensive approach to the analysis of the object and subject of research, which covers philosophical and legal methods – dialectical method of scientific knowledge, system-structural method, empirical method, hermeneutic method, synergetic and formal-legal methods of scientific research. As a result, the growing role of international organizations as subjects of interpretation, which do not only play an essential role in international law-making and the implementation of international law but also take an active part in their interpretation, was proved. In interpreting their charters, international bodies and organizations certainly influence the content of other international norms. At the current stage, it is necessary to define international organizations’ interpretive activity as a particular type of international law-making, which consists in the official interpretation of international legal rules contained in the relevant acts. Nevertheless, they do not acquire the status of law-making bodies, and their decisions and conclusions are of a recommendatory nature.