Sacred Islamic jurisprudence, with its favorable richness, is the main source of criminal law in Iran. Some critics and critics have introduced Islamic jurisprudence as strict because of its repressive treatment of criminals; Whereas, Islamic penal jurisprudence teachings are full of principles to protect the rights of accused and criminal; Among these principles, we can mention the principle of interpretation of criminal laws in favor of the accused, based on which, whenever there is ambiguity and doubt in understanding the meaning of the text of criminal laws; That vague text should be interpreted in such a way that it includes "the benefit of the accused". This principle has a great impact on the protection of the accused and shows that Islamic penal jurisprudence does not seek mere punishment in any way. Considering the need to introduce penal jurisprudence as the basis of such modern principles; This article explains the principles of criminal jurisprudence related to the principle of interpretation in favor of the accused with a descriptive-analytical method and a library tool, so that how this principle derives from the principles of Chezai jurisprudence can be clearly identified. In this regard, the principle of interpretation is in favor of the accused from the point of view of the rule of law, the principle of guilt and the principle of acquittal; It has been explained and explained, and in the end, it has been concluded that the principles of criminal jurisprudence with the principle of interpretation in favor of the accused, tolerance and tolerance of humanitarian rights have been used for the accused in their time, which are applicable for all times and places.