The objective of this article is to study political changes in the Korean Peninsula in 550s and trends of Yamato Wa. Baekje asked Yamato regime five times to provide military assistance to prepare for the war against Silla, but Japan did not immediately provide its soldiers and only sent about 1,000 soldiers. At that time, Baekje was in a situation where it had to receive military support for its national interests. It was also intended to make Silla and Goguryeo aware of the diplomatic relations of Baekje and Yamato Wa regardless of the size of the military assistance. On the other hand, the Yamato Wa focused only on the means of receiving advanced cultural support from Baekje. While sending as few of its soldiers as possible for the national interest, the Yamato government sought to receive a large amount of advanced cultural support from Baekje. It is also believed that the Yamato regime at that time was reluctant to request from Baekje due to domestic circumstances such as the formation of the new dynasty and the confrontation of major clan forces. In addition, the supply of troops was not provided by the Yamato regime but by the individual clan support system.