Immanuel Kant builds his reason of education on the basis of the realization of the "adulthood" of human and the "Enlightenment" state of humanity. In his aspect, human being is the only being that needs to be educated because he comes to the world as primitive and wild. In this respect, to Kant, education has a significant function in the perfection of human nature. Some basic educational practices that are consisted of discipline, acculturation, civilization and moralization are required for the free and autonomous individual to grow up, which is one of the indicators of human adulthood. Kant states that a person who has an innate tendency towards goodness should be disciplined before he/she gets used to bad habits related to arbitrary freedom. For this reason, discipline, which is critical for a moral education based on Maxim, is one of the essential processes for the realization of the aim of the free and autonomous human ideal. Because, while the lack of knowledge can be compensated in any period of human life, it is difficult or impossible to correct some negative habits that are caused by lack of discipline and become a character. In the study, the place and importance of the concept of discipline, which is accepted as a pre-stage of acculturation, civilization and moralization, in Kant's reason of education will be tried to be revealed. Through this study, -even partially-, there will also be contributions to the search for the answer to how the human being ascension to a moral being will be and where it will start