The article deals with the formation of harmonized legal framework as part of integration associations of Eurasia and Latin America. The article states that harmonization and unification of private international law is of particular importance for achieving the objectives of economic integration. The authors analyze the methods of harmonization of law in Mercosur. Harmonization of law is achieved in various ways, for example, through unification of law which permits to develop a uniform enactment for all States. Meanwhile, the method of simple convergence, coordination of national legislation of the Mercosur member states is used. The authors distinguish between the sources of primary and secondary law of the Eurasian Economic Union. The authors conclude that unlike the Commonwealth of Independent States where unification and harmonization cover private and public law, the convergence of legal systems of the member States of the Eurasian Economic Union deals mainly with public law issues. Along with strict public law regulation within the Eurasian Economic Union, the authors propose the formation of flexible private law rules contained in the soft law, and the Principles of the Eurasian private law can serve the basis for that. The authors note that one of the objectives of harmonization and unification of the law of integration associations is the formation of the community law – an autonomous legal system which is applied on the basis of the direct action principles, direct application and the supremacy over domestic law. Following the results of study the authors conclude that the majority of the integration associations in Latin America and Eurasia are only on the way toward the community law formation.