Law ideology of the post-soviet states that have been participating in market conditions of social and economic development and that have declared themselves by the constitution as social may seem equal. However, their law systems are not the same. Development of interstate interaction in the frames of the Union State of Belarus and Russia as well as the EAEU requires deep harmonization of the law systems of those countries. Socialization may serve as institutional platform of the law systems harmonization. The idea of socialization was born in Europe in the end of the XIX century. Its purpose was to curb bourgeois individualism and egoism. Nowadays it has been transformed in the direction of balanced combination of interests of all the layers of the society, its partners and collaboration. When applied to the conditions of the modern state of law systems of the post-soviet states, if we take the civil law as an example, main principles of its socializations are described. There are the following principles that are related to the basis of the subject of the civil law: the unity of property and personal non-property relations; interdisciplinary approach to the regulation of civil relations; intersectional legal regulation of civil relations. The main basics of the methods are the unity of the general scientific and civil legal methodology; solidarity, parity, coordination of rights, obligations and legal interests of the person, second parties and society; individualization and specification of civil relations. Other elements of the system of the civil law should be based on the following principles: interconnection of the institutions and other elements of the system of the civil right; the indissoluble connection of an indefinite number of civil legal relations; unity of civil rights and obligations, permissions, prohibitions and regulations.