According to Article 91 of the Islamic Penal Code, criminal liability for hadd crimes and retribution for persons under 18 years of age is subject to the achievement of criminal maturity. This research, based on the type of research, is fundamental; based on the method of investigation and answering questions, it is descriptive; and based on the method of information collection, it is library; has addressed the necessity of establishing maturity in criminal matters and its evidence. Although in religious texts, the beginning of criminal liability is stated from the time of puberty, some public jurists have considered it necessary in determining the duty, considering the verses related to mature puberty, growth and intellectual perfection, which begins at the age of 18. In the narrations transmitted through the Imamiyyah, the application of the title of foolish and weak in narrations also includes persons who lack maturity, and also, according to the narrations that have relieved responsibility from an insane and insane person; in connection with the ruling and the subject, criminal liability has also been relieved from persons who lack maturity due to the lack of understanding of the nature of the crime and its sanctity and doubt in intellectual growth and perfection. In addition, on the one hand; It is not possible for immature individuals to commit a voluntary act or criminal intent due to their lack of understanding of the nature of the crime and its sanctity. On the other hand, the existing necessities and the need to respond appropriately to the crimes of children indicate the non-implementation of the punishment of hadd and qisas, as punishing such individuals will not achieve the goals expected by the legislator.