In 1933, the Kwantung Army invaded the Jehol province of China. Just after that, the Manchoukuo government commissioned architectural historians to survey the "Heritage of Jehol". On the basis of this survey, the government established the survey and restoration office on the site due to the preservation of this Heritage in 1935. This paper tried to grasp some of Cultural Policy in the Japanese Colony during a prewarperiod. The subject of considered are as follows : 1) Investigation activities of the Heritage by historians. 2) Investigation and preservation activities of the Heritage by the preservation architects. 3) A way of Cross-Cultural Understanding by architects and architectural historians.