The insertion portion 2, the high-frequency knife, the suction pipe 10 for sucking fluid from the suction port 6s, the bypass pipe 15 through which the gas D containing the component derived from the living tissue passes, and the suction pipe 10 at the position 10y The provided suction button 3a for opening and closing the flow path of the suction pipe line 10, the electromagnetic valve 17 for opening and closing the flow path of the bypass pipe line 15, and the valve for opening and closing the electromagnetic valve 17 based on the operation of the high-frequency knife And an opening / closing part 34a.挿入部２と、高周波ナイフと、吸引口６ｓから流体を吸引する吸引管路１０と、生体組織に由来する成分を含む気体Ｄが通過するバイパス管路１５と、吸引管路１０において位置１０ｙに設けられた、吸引管路１０の流路を開閉する吸引釦３ａと、バイパス管路１５の流路を開閉する電磁弁１７と、高周波ナイフの動作に基づき電磁弁１７に対して開閉動作させる弁開閉部３４ａと、を具備する。
