Abstract: The type locality of the Menggon’ao Formation is near Menggong ’ao, Jieling Township,Shaodong County,Hunan, Lying above the Yuelushan sandstone or Xikuangshan Formation andbelow the Malanbian Formation,this formation is represented by a mixture of terrigenous clasticrocks and carbonate rocks,consisting mainly of shale and sandy shale with siltstone and bioclasticlimestone,It belongs to the upper part of the Famennian stage in central Hunan and its upperboundary is in the main consistent with the disappearance of the corals Cystophrentis,while insouthern Hunan and northern Guangdong its upper boundary is below the range-zone of Cystophrentis.