Abstract: The stratum feature and distribution of the Brachiopod. Fusulinidea faunas of the Benxi Formation and the Taiyuan Formation in Dongshan, Taiyuan were reseached. The boundary between the Permian and Carboniferous systems was discussed. Because the flourishing of Brachioghs and the appearance of Chalaroschwagerina are accost the same time of the appearance of Psedoschwagerina, it is believabe that the nourishing of Brachiopods and the appearance of Chalaroschwagerina can be regarded as the begining of Penman when Pseudoschwagerina is absent. Thus the the between the Permian and Carboniferous systems can be drown at the base of the Jiandaogou limestone in Dongshan, that is, the Taiyuan Formation belongs to the late Carboniferous to early Permian in age.