PROBLEM TO BE SOLVED: To provide a thresher including a threshing cylinder freely rotatably disposed in a threshing chamber, and a threshing port for carrying mown grain culms in the direction of the rotating axis of the threshing cylinder with the heads of the mown grain culms being inserted into the threshing chamber, in which a piercing preventing body has a function of preventing straw scraps from clogging as well as excellent durability while effectively preventing grains from piercing grain culms.SOLUTION: A piercing preventing body 30 that catches threshed products, scattered in a threshing chamber 2, above mown grain culms C inserted into the threshing chamber 2 and causes them to flow in the direction of a threshing cylinder is disposed in a freely elastically deformable manner inside a threshing port 14 in the threshing chamber 2. The piercing preventing body 30 includes notches 32 opening facing the threshing cylinder 10 so that threshing teeth 10b of the threshing cylinder 10 can pass therethrough. The threshing teeth 10b each enter into each of the notches 32 to the extent of a length L1 which is equal to or longer than a half of the length L of the threshing teeth 10b protruding from the threshing cylinder drum 10a.COPYRIGHT: (C)2013,JPO&INPIT【課題】扱室に回転自在に設けた扱胴と、刈取り穀稈の穂先側を扱室に挿入して扱胴の回転軸芯に沿う方向に搬送する扱き口とを備えた脱穀機において、穀稈の穀粒ささりを効果的に防止できながら、ささり防止体にワラ屑詰まりの回避機能と優れた耐久性とを備えさせる。【解決手段】扱室2に飛散した脱穀処理物を扱室2に挿入された刈取り穀稈Cの上方で受け止めて扱胴側に流動させるささり防止体30を、扱室2における扱き口14の内側に配置して弾性変形自在に設けてある。ささり防止体30に、扱胴10の扱歯10bが通過するよう扱胴10に向かって開口した切欠き32を設けてある。扱歯10bがこれの扱胴ドラム10aからの突出長さLの半分以上の長さL1にわたって切欠き32に入り込む。【選択図】図4