The purpose of this paper is to study the process of the settlement of Korean farmers in Japanese villages in the prewar period.There have been few researches about this subject because of an insufficiency of historical materials, and a recognition that Japanese villages are ethnically homogenized community also prevented researchers from investigating on this important issue.In particular, we argue two problems in this paper.The first is to show the process of the settlement of Korean people as agricultural labor through 1920s.With the modernization of Japanese agriculture, the number of agriculture labor, especially annual labor was decreased.But the rest was being altered by Korean people gradually.It is analyzed in a case of Kyoto Prefecture using the bookkeeping for farm household as primary resources.The second is to show the actual condition that the number of Korean tenant had sharply increased in WW2 period.It is proved using Ministry of Agriculture and forestry ex-confidential document covering the greater part of Japan in 1943.Although Japanese government had thought this phenomena serious, they hidden the data and did not make a clear policy.Therefore, regional governments decided on a basis of their own standard.The "rooting" of Korean people is not just an exceptional event.The adoption of foreign people meant that Japanese rural community partly varied to multi-ethnical community.Japanese administration had try to stop this tendency secretly and did unclear discrimination against Korean farmer.On the one hand they did ruthless assimilation policy on people under the colonial rule, on the other hand they try to keep the ethnic homogeneity of Japanese rural society.This was just a contradiction of Japanese empire.These results would urge us to study this alteration of Japanese villages along with the relevance to the Japanese colonial landownership and rural exodus under the Japanese imperial sovereignty.This issue is an important subject to overcome our "national history".