To understand the essence of a legal system, one of the priority tasks is to study the doctrine of its sources of law. The situation with Islamic law is similar. The doctrine of sources of law is one of the most developed because it has been studied by a large number of lawyers and orientalists. At the same time, we see insufficient research on this doctrine due to a large number of approaches to understanding the term «source of law». In this paper, we have explored the sources of Islamic law in accordance with the Twelvers madhhab, as it is a basic school of Shiite legal doctrine. As a theoretical basis for the analysis of approaches to understanding the «sources of law», we have chosen approaches and their characteristics that would cor...