The roots of rhetoric and legal sciences go back to ancient times and at certain stages of evolution, rhetoric and law had both links and intersections. At different times, their union was treated differently -sometimes it was encouraged, and sometimes -not at all. In the long run, however, it has been understood that legal dogmas alone do not describe all life events, so it is necessary to take certain circumstances into account each time, and rhetoric can help to articulate and convince the court of them. Its art of persuasion has always been associated with wise and reasonable speaking, giving the one explaining a certain point the right and freedom of speech allowing to explain legal norms, evaluate and interpret them and persuade listeners of them. So the objective of the article is to analyse the origin and development of the relationship between rhetoric and law. Used analysis and synthesis of scientific literature and analytical methods helped to analyse the main links and intersections of rhetoric and legal sciences at different stages of their development and assess the differences and circumstances of said stages that led to them. A review of the origins and development of rhetoric and law shows that each of them have their own history of origin, but in certain periods of their development, obvious links and intersections, determined by certain historical changes, could be noticed. In view of the diverse environment in which rhetoric and legal interfaces and intersections are treated, it must be acknowledged that each of them is a separate science with points of contact, but it must be acknowledged nonetheless that rhetoric was recognized as important to law as a representative of democracy and freedom of speech, and the main task of rhetoric -to persuade the listeners in wise and reasonable language, and help maintain the unity of law and justice. Thus, modern rhetoric teaches speakers to be effective persuasors in courtrooms, using both legal facts and the art of eloquence in a broad sense.