Introduction. The article highlights the main milestones of the professional development of Kharkiv University professor A. Stoyanov and his scientific activity in the field of history of law. It was found that modern researchers who, in the course of their scientific research, turned to the analysis of his works, for certain reasons, emphasize primarily the work of the scientist in the field of international law, but usually do not pay any attention to the extremely wide range of historical and legal research of the scientist, which in his scientific creativity, he himself took far from the last place in terms of importance and volume. This is what determined the topic of this article. Summary of the main results of the study. It is noted that one of the most interesting historical and legal works by A. Stoyanov's monograph "History of Advocacy among Ancient Peoples", in which the monuments of law and legal thought of Egypt, India, ancient Jews, Greeks and Romans were analyzed. The embryo of the Institute of Advocacy A. Stoyanov saw precisely in the ancient Greek synegory. His historical and legal studies "Historical analogies and points of intersection of new legislation with ancient law", "The beginnings of family law among primitive peoples", "Family law and inheritance among Jews" and published by the publishing house of Kharkiv University in separate brochures aroused considerable interest among scientists and students of that time, "Family, marriage, and the legal position of women according to the legislative monuments of India", "Customary law in the history of the most important states of Europe and especially France", "Customs of society and courts in France from the end of the 17th century. until 1789". A certain result of this stage of his studies of ancient law was the publication of the author's lectures devoted to the history of the legislation of the countries of the East. Some scientific research carried out by Professor Stoyanov at one time caused heated discussions and controversies. Among these, first of all, we can mention the work "Historical analogies and points of intersection of new legislation with ancient law", which was published in 1883 and was an extremely interesting attempt at diachronic comparative research, one of the first that was carried out in the universities of Eastern Europe. He was an ardent supporter of comparative and especially historical methods of studying legal institutions. He used them widely when writing his scientific works. The scientist published a significant part of his works in the journal "Notes of the Kharkiv University". One of the most interesting historical and legal studies, which has not lost its relevance even today, is the work "Criminal Law of Rome from the earliest times to Justinian inclusive", published here in 1895. Conclusion. The conclusion that A. Stoyanov was a bright representative of that generation of lawyers of the Kharkiv school, whose work created the foundation of the modern national science of the history of law. His works, which during the Soviet era were forgotten for ideological reasons and only briefly mentioned by researchers, contain many layers of valuable historical and legal information and deep scientific conclusions. The merits of the scientist in the future have yet to be fully assessed by the next generation of lawyers.