Abstract: There exists an unconformity between the Theshanling Formation and the Tanzehe Forma-tion of the Taihua Group in the Lushan area,Henan,On the basis of the rocks and structures andage data of the Taihua Group,the stratigraphic sequence of the group has been redefined.The o-riginal Taihua Group is all assigned to the Taihua Supergroup.With the unconformity as theboundary,the upper part is called the upper Taihau Group, including the Xuehaugou Formation,Shuidigou Formation and Tieshanling Formation, and the lower part is called the Lower TaihuaGroup ,including the Tangzehe Formation and Naizhuang Formation.