The Yamatai Honshu Theory is the theory that the Yamatai kingdom was located in Honshu, specifically Kinai, where the capital was located in the Kofun period rather than in Kyushu as the Yamatai Kyushu Theory proposes.

The Yamato Kingship was a tribal alliance centered on the Yamato region from the 4th century to the 7th century, and ruled over the alliance of noble families in the central and western parts of the Japanese archipelago. The age is from the 4th to the 7th century, later than the Yamatai Kingdom. After the Taika Reform, the ōkimi as an emperor, at that time, was in power, and the Yamato period ended. The time period is archaeologically known as the Kofun period. Regarding its establishment, due to the relationship between Yamatai and Yamato's succession to the king's power, there are very different views on it.