Treatment and rehabilitation is one of the important issues facing the criminal policy. The purpose of this article is to examine treatment and rehabilitation in Iran's legal system from the perspective of criminal policy. This article is descriptive and analytical. The materials and data are also qualitative and data collection has been used in the collection of materials and data. Correctional behavior with criminals and choosing the most suitable solutions, seeks to rebuild their personality and prevent the repetition of crimes. Reforming criminals in its various meanings is a humane approach to dealing with crime and delinquency, which is also considered in Iran's criminal policy. Therefore, the prison should be ready to provide services to the prisoners as a place of reformation and rehabilitation to return to the society and not as a dangerous place. In Iran's legal system, under the influence of transnational criminals has undergone changes from before the revolution until today, which has led to the humanization and improvement of the rights of criminals. of human rights in the direction and rehabilitating criminals, the domestic laws of the countries also underwent a tremendous transformation. Under the influence of other transnational laws, in the second generation of human rights, human dignity and respect for the rights of prisoners were placed at the top of the pyramid of the criminal justice system and caused the humanization of the view and action in line with the protection of the rights of prisoners.