In this article, data of bronze and iron objects unearthed from the prehistoric sites in the area of Southeast Mainland China are analyed by means of the distribution of their site locations, dates, quantities and types, and then the movement of comtemporary culture is inferred. As to the conclusion, the elements of the Chung-yuan Culture that had already reached to the northern and central Chiang-hsi, had spread even to the coast of Fu-chien during the Shang-Chou period, because of geographical contiguity, i.e. the result of natrual contact. However, in Chunchiu-Chankuo period, the Chung-yuan elements also rushed into Kuang-tung area, which could be the outcome of social forces such as political and economic ones. In terms of the above analysis, the cultural relations between Taiwan and the southeastern coast of Mainland China at that time could also be a kind of natural contact caused by geographical contiguity.