Ideas about the alleged genetic relation between the Japanese and the Jews appeared at the end of the XVI - beginning of the XVII centuries when the first wave of Christian missionaries came to Japan. Western missionaries were so amazed at the level of education, intellect, and cultural development of the Japanese, that they could not believe in their Far-Eastern origin. Thus, in the missionary circles there emerged an idea of a specific relation of the Japanese to the ten lost tribes of Israel. Later, in the second half of the XIX century, some missionaries of the second wave also adopted this concept. Since then the acknowledgement of a close spiritual, if not genetic relation between the Japanese and the Jews has become one of the main doctrinal elements in a number of Japanese Christian organizations, mostly of a relatively marginal character. This concept is easily discerned in the thought of such prominent Christian leaders as Uchimura Kanzo, Yanaihara Tadao, Nakada Juji, Teshima Ikuro, Otsuki Takeji, Saeki Yoshiro, and so on. The article aims at analyzing the transformation of the idea of the close spiritual connection between the Japanese and the Jews in various Christian organizations in Japan, searching for the reasons for this concept to develop, and exploring its adaptation to the contemporary situation in Japan.