Abstract: The paper reports a new genus of Arcypteridae I.e.Suacris gen.nov.and a new species Suacris siyangensis sp.nov.The new genus is similar to Omocestus I.Bol.,but differs from the latter in:1)Lateral carinae slightly curved,widest 1.6-1.8 times greater than narrowest.2)Cubital area wider than or equal to medial area.3)Tympanum organ distinct,♂ widely oval,♀ crevice-like.The new genus is also similar to Stenobothroides Xu et Zheng,but differs from the later in:1)Lateral carinae obvious and curve.2)Ter gum of terminal abdomere without furcula.3)Male subgenital plate long conica.Typ e specimens are deposited in Northwest Plateau Institute of Biology,the Chinese Academy of Sciences.