Due to modernism in the first Pahlavi era, numerous apparent and fundamental changes in the social life of people, such as the change or replacement of traditional and typical institutions with new Western-patterned organizations and the emergence of the new mechanism in the pillars of the government happened. The dismantling of Iran’s traditional justice system and dissolution of Adliah in several stages and the establishment of modern justice system – which, in addition to modernism, aimed at concentrating the power in the pillars of government and removing the influencing local and traditional institutions such as clergy – had a significant impact on people’s life. It was met by reactions and opposition from some social classes. The present research, which has been done through a library and descriptive method, tried to study these reactions based on the official documents and formal letters leftover from that period. The research findings showed that, despite the imagination of other researchers, the dismantling of the traditional justice system and the dissolution of the Adliah was in three stages and it has been met by reactions and oppositions of some political elites and influential classes such as lawyers, judges, Adliah officials, Parliamentarians and some weaker social courses such as residents of some cities and even some religious minorities.