Abstract: This article examines the role of socialization in the process of personal becoming and development, as well as raises the question of whether or not socialization process is an essential condition for personality formation. The author considers and compares the three stages of personal becoming: an individual (natural, genetic-biological aspect), individuality (psychological aspect), personality (social aspect); as well as the three paramount spheres of socialization: activity, communication, self-consciousness. It is determined that the activity forms individuality of a person, and the social activity forms personality. Such sphere of socialization as communication has an equally significant impact upon all stages of personal development. The sphere of self-consciousness forms along with the process of personal becoming. The fundamental principles of dialectics and activity approach, analysis, generalization, and comparison are applied. The study is structured on the basis of apprehension of the activity nature of a person, which is the foundation of his becoming and development in society. The conclusion is made that socialization process at different stages of social development has its peculiarities, which also manifest in the three described spheres: activity, socialization, and self-consciousness. Examination of the specificities of formation of the aforementioned spheres of socialization allows drawing parallels and concluding on the process of personal development at its various stages (individual, individuality, personality) in the context of a particular historical segment.