The middle Viséan coral biostrome from the Shangsi For-mation at Yashui, which is variable from 2.5 m to 3.9 m inthickness and more than 500 m in width, is composed mainlyof Kueichouphyllum (solitary rugose coral), Syringopora,and Siphonodendron. Associated fossils include brachiopods,crinoids, foraminifers, calcareous algae, gastropods, bryozoans,and ostracodes. In the biostrome, three growthstages have been distinguished, which in ascending order areKueichouphyllum growth stage, Kueichouphyllum-Syringoporagrowth stage, and Siphonodendron growth stage. The biostromeoccurred at shallow DQGX platform margin with its growthand demise controlled by relative sea-level rise and fall, asevidenced from the increasing of micrites and sparry calcitein the biostrome and its overlying limestone, respectively. Compared with the coral reefs, the coral biostromelacks calcimicrobe encrustation and sparry calcite cementation