A high-frequency treatment instrument includes a flexible tube for insertion into a body cavity, an operating wire inserted through the flexible tube so as to freely move back and forth, a treatment element provided at a distal end of the operating wire so as to treat body tissue by applied high-frequency current, a main body immobilizing a basal end of the flexible tube, a slider fixing means immobilizing the basal end of the operating wire which is derived through a basal end of the flexible tube so as to slide the operating wire relative to the main body along a direction of long axis, and a slider gripping means provided as to at least partly surround an outer periphery of the slider fixing means so as to slide the slider fixing means by an operation of a user, wherein the slider fixing means is unrotatably connected to the main body and the slider gripping means is rotatably connected to the slider fixing means.本發明之高頻處理具包含:可撓管,其插入體腔內;操作導線,其進退自由地插通於可撓管內;處理部,其配置於操作導線之前端側藉由高頻電流之施加而處理活體組織;本體部,其固定可撓管之基端側;滑件固定部,其固定自可撓管之基端導出之操作導線之基端側,且使操作導線相對於本體部向軸線方向滑動;及滑件抓持部,其環繞滑件固定部之外周面之至少一部分而設置,藉由使用者之操作使滑件固定部滑動;且滑件固定部相對於本體部不可旋轉地連結,滑件抓持部相對於滑件固定部自由旋轉地連結。100‧‧‧操作部110‧‧‧本體部111‧‧‧槽孔113‧‧‧內管114‧‧‧基端鉤部121‧‧‧連接部122‧‧‧旋轉部123‧‧‧供電端子124‧‧‧固定接腳125‧‧‧端子固定部127‧‧‧貫通孔130‧‧‧本體操作部140‧‧‧滑件抓持部150‧‧‧滑件固定部151‧‧‧第1固定部152‧‧‧第2固定部153‧‧‧第1突片154‧‧‧第2突片160‧‧‧端子蓋170‧‧‧指扣部171‧‧‧內槽180‧‧‧導電性管200‧‧‧可撓管
