A new lithostratigraphic unit, the Hesheng Formation, is erected to represent Cisuralian (Lower Permian) terrestrial strata characterized by the Cathaysia flora in the Yanbian area, JilinProvince. The type section of the formation is the Heshengcun section in the vicinity of Hesheng Village of Daxinggou Town, WangqingCounty. The Hesheng and Dasuangou formations constitute a Cisuralian-Guadalupian transgressive sequence on the northern margin of the North China Plate. Biostratigraphic evidence suggests that the Hesheng Formation is of Late Cisuralian (Artinskian-Early Kungurian) in age.