A surgical instrument (1) includes an insertion section (2), a surgery section 3 provided at a distal end of the insertion section (2), and a manipulating section (4) provided at a proximal end portion of the insertion section (2). The surgery section (3) has a pair of grip sections (101, 102) which are relatively openable, and a turning section (84) which turns an orientation of the grip sections (101, 102) in a direction deviating from an axial direction of the insertion section (2). A heating member (124, 125) which generates heat by power supply is arranged at least one of the grip sections (101, 102). The manipulating section (4) has an opening-and-closing manipulating section (4b) which opens and closes the grip sections (101, 102) and a turning manipulating section (4a) which turns the turning section.
