An analysis of written historical sources that have survived to this day shows that judicial precedent is the oldest source of law. At different stages of the development of human society, the judicial precedent was to one degree or another the regulatory carrier of the relations that arose in it. This regulation is carried out from concrete to abstract, and therefore can occupy a special place in the legal system of society. This served to group national legal systems into legal families, which are united by the commonality of both the basic concepts, the structure of law, and the sources of law. Judicial precedent is an act of law-making, which is adopted in a certain order by a government body empowered to administer justice. Judicial precedent can be one of the main regulators of social relations, and have a secondary, insignificant role in the formation of sources of law in a separate legal system of a specific state. Thus, in the Anglo-Saxon legal family, court precedents traditionally refer to the main, dominant sources of law. The paper is devoted to the issue of the essence and role of court precedent as a source of law in the countries of the Anglo-Saxon legal family. It is established that the doctrine of judicial precedent is applied in England due to a historically formed legal tradition, and in the countries of the Anglo-Saxon legal family - due to the dominant influence of England on them in certain historical periods. In many ways, the doctrine of judicial precedent has demonstrated its success due to public legal awareness and the high level of professional skill of judges who lead the judicial system. It is they who form precedent law in general. The ratio of precedent and law, with the significant predominance of the former over the latter, led to the primacy of the judiciary over the executive. Quite often in the countries of the Anglo-Saxon legal family, a rule that derives from the law is unfit for practical application until it is explained by a judge. Thus, judges act as interpreters of laws, and court precedents, to a certain extent, as «commentaries on laws». The construction of judicial precedent has both positive and negative aspects. Even within the parent countries of the Anglo-Saxon legal family, not to mention mixed legal families, judicial precedents are applied differently, which indicates their adaptability, and therefore the ability of judicial precedent to be useful for Ukraine.