This study is an analysis of the aspects of international cultural exchange in the private sector by 'interactive cultural interchange' and 'multilateral transculturation', that appears in cultural exchanges between Korean private cultural organizations and the Utagoe movement in Japan. The current international cultural exchange in the private sector differs from the one-way international cultural exchange between countries in various aspects in the past. First, in the interactive cultural interchange, subjects in an equal position not only interchange cultural actions, but also actively interchange the inner meaning of the actions. Furthermore, in the case of cultural exchange between a Korean private cultural organization and the Utagoe movement in Japan, it shows that the continuous interactive cultural interchange develops into a multilateral transculturation. Second, various multilayered groups are intertwined through cultural exchanges, resulting in multilateral transculturation. The Korean cultural organization and the Utagoe movement in Japan created a new culture of coexistence as mutual communication occurred due to transculturation. This culture of coexistence by each other can be created and influenced between groups, resulting in substantial group changes. As shown by the Korean private cultural organization and the Utagoe movement in Japan, international cultural exchange in the private sector does not appear as a separation of interactive cultural interchange and multilateral transculturation. Interactive cultural interchanges can occur simultaneously or sequentially as they change into multilateral transculturation, and interchanges and crossings are mixed and intermediate.