A depositional hiatus of five graptolite zones, between the Paraorthograptus pacificus Biozone and the Coronograptus cyphus Biozone, is recognized based on biostratigraphical and lithological evidence at the Dengcaoping Ordovician-Silurian Section, Taiyanghe, Enshi, Hubei Province. The abundance of kaolinitein the claystones between the Ordovician and the Silurian rocks implies that the study area had probably emerged above the sea level during the depositional hiatus. The geological processes before and after this hiatus can be described in this paper. The sea level fall in this area is thought to be a related to the late Katian-early Hirnantian global regression and the continuous west to northwestward expansion of the Cathaysian Land.