A large number of fossil plants were collected for the first time near the Hesheng Village of Daxinggou Town of Wangqing county, Yanbian area, Jilin province, Northeast China. The strata bearing these fossil plants are terrestrial sediments dominated by dark grey fine-grained sandstone, siltstone and mudstone. These sediments were thought to be marine and assigned to the Guadalupian Miaoling Formation and the Guadalupian Sidonggou Formation in 1966 and 1991, respectively. The strata are considered as a new lithostratigraphic unit and named as the Hesheng Formation by authors currently. The fossil plants of the Hesheng Formation consist of 30 species of 18 genera, namely Lepidophylloides sp., Stigmaria ficoides(Sternb.) Brongn., Trizygia oblongifolium (Germ. et Kaulf.) Asama, Calamites cistii Brongn., C. sp., Paracalamites stenocostatus Gu et Zhi, Annularia stellata(Schloth.) Wood, A. sp., Schizoneura sp., Sphenopteridium pseudogermanicum (Halle) Sze, Sphenopteris rotunda Sze, Pecopteris arborescens(Schloth.) Sternb., P. candolleanaBrongn., P. cyathea(Schloth.) Brongn., P. huichensis Hsü, P. marginata Gu et Zhi, P. cf. P. (Asterotheca) orientalis (Schenk) Pot., P. yabei Kaw., P. sp., ovata Hoffm., N. plicataSternb., Odontopteris subcrenulata(Rost) Zeill., Taeniopteris cf. T. multinervis Weiss, T. yernauxii Stockm. et Math., Emplectopteris sp., Cordaites principalis (Germ.) Gein., C. schenkii Halle, Cardiocarpus sp., Rhabdocarpussp. and Radicites sp. This flora (Hesheng Flora) is dominated by ferns and seed ferns which take more than 50 percent of the total number of species. These ferns and seed ferns are characterized by diverse Pecopteris, Sphenopteris, Neuropteris and Taeniopteris. Moreover, Sphenopsids take more than 20% of the total number of species in the flora, and are characterized by Calamites, Paracalamites, Annularia and Trizygia. Thus, on the floristic composition, the present flora is similar to the wellknown Emplectopteris triangularisEmplectopteridium alatum assemblage of the Shanxi Formation in Shanxi Province, China. There are four types of floras in China during Permian. Among them, the Cathayasia flora is mainly distributed in three floristic areas in China, i.e., the northern China, northwestern China and southern China. Among the 21 known species of the Hesheng Flora, all of them are recorded in the northern China floristic area, and 17 species in the Northwestern China floristic area, and 12 species in Southern China floristic area. This indicates that the Hesheng Flora has a typical Cathaysia floristic character. Furthermore, most species of the Hesheng Flora are important or peculiar elements of the Cathaysia flora, such as Emplectopteris, Odontopteris subcrenulata, Taeniopteris yernauxii, Pecopteris huichensis and P. marginata; whereas there are no typical Angara elements, such as Angaridium, Cardioneura, Rufloria and "Neoggerathiopsis". Therefore, the Hesheng Flora is definitely of Cathaysia floras in nature. Since most species of the Hesheng Flora are common in the Taiyuan and Shanxi formations in northern China, and some are even only found in the Shanxi and Xiashihezi formations in northern China such as Sphenopteris rotunda, Pecopteris marginata, P. yabei, Odontopteris subcrenulata, Taeniopteris yernauxii and Paracalamites stenocostatus, the Hesheng Flora is considered as late Cisuralian of Permian (Artinskianearly Kungurian) in age. The discovery of this Cisuralian flora shows that the distribution of Cathaysia flora should extend northward to the Daxinggou district in Wangqing County, and that the boundary between the Cathaysia flora and the Angara flora is probably located in a narrow northwestward zone geographically ranged from the Kaishantun of Yanji CityDaxinggou of Wangqing County to the Jiefangcun of Hunchun City-Shiliping of Wangqing County. This is beneficial not only for the study on the boundary between North China Plate and Jiamusi-Mongolia Block, but also for the research on the eastern part of Xar Moron River suture zone in Yanbian area on the paleobotanical basis.