The article is devoted to the analysis of the formation and development of academic research in the field of international law at Koretskyi Institute of State and Law. Organizational origins of international law started with the creation of the state and legal sector in the system of the National Academy of Sciences of Ukraine in 1949. Special attention is paid to the role of the outstanding student of international law in the creation of the Institute of State and Law, organization and implementation of legal research, in particular in the field of international law and the formation of the relevant scientific school. The objective development of international law in the second half of the 20th century was conditioned by the necessity of ensuring the international legal activity of Ukraine in the international arena, as one of the founding members of the United Nations. At this stage, the efforts of Koretsky and his associates were directed at the theoretical substantiation of the international legal standing of Ukraine, the study of the problems of the codification of international law, its sources, and the relationship to the internal law of states. The results of fundamental research in the field of international law contributed to the recognition of Ukrainian scholars to international legal science. Koretsky was recognized as one of the world’s leading figures and attracted by the international community to practical international legal activities in specialized United Nations bodies. He entered history as one of the founders of the Universal Declaration of Human Rights. In the 1950s and 1960s, the development of Ukrainian international law was characterized by the active formation of its scientific school, the most prominent representatives of which were M. Mikhailovsky, N. Ulyanov, V. Sapozhnikov, etc. Their research has laid the foundation of the modern school of international law. The article analyzes their main works and theoretical positions that have become the patrimony of international legal science. During the 1970s and 1980s, the development of international legal science in Ukraine were characterized by the growth of its scientific potential, personnel growth of the school, expansion of the range of research. Since 1984, the position of Head of the Department of International Law and Comparative Law of the Institute has been held by V. Denisov, who ensured the organizational and methodological framework for studying relevant problems of international law. With the proclamation of Ukraine’s independence, the main tasks of the national science of international law are aimed at studying the problems of the implementation of the sovereignty of Ukraine. Over the past three decades, the results of research by scientists of international lawyers of the Institute have become dozens of individual and collective monographs that identified the main trends in the development of science of international law at the present stage. Today, the scientific school of international law is represented by such doctors of law as V. Denysov, V. Akulenko, O. Kresin and candidates of jurisprudence O. Didkivska, O. Pereverzeva, I. Protsenko, K. Savchuk, A. Smolii, M. Surzhinskyi, L. Falaleyev. A special attention in the article is devoted to the analysis of organizational and scientific activities of the directors of Koretskyi Institute, namely academicians B. Babiy and Yu. Shemshuchenko. Keywords: international law, school of international law, Institute of State and Law, scientific researches, international legal activity, stages of development of the school of international law.