A surgical therapeutic instrument comprising: an insertion unit (2, 1002); a treating unit (4, 1004) that is arranged at one end of the insertion unit (2, 1002) to be extended in an extending direction at a predetermined angle to the axial direction of the insertion unit (2, 1002); an operation unit (3, 1003) that is arranged at the other end of the insertion unit (2, 1002); a rotating operation unit that is arranged to the operation unit (3, 1003) to rotate the treating unit (4, 1004); and an opening/closing operation unit that is arranged to the operation unit (3, 1003) to open/close the treating unit (4, 1004), two pinching members (1035, 1037, 1084, 1089, 1212, 1212a, 1212b) that are provided at the treating unit (4, 1004), each of the two pinching members having a planar portion surface (1214a, 1216a, 1035b, 1037a, 1057a, 1084a, 1089a), wherein the planar portions surface (1214a, 1216a, 1035b, 1037a) of the two pinching members (1035, 1037, 1212) are configured to pinch a needle therebetween when the pinching members are in a closed state; a wedge member (1204, 1081a) that has a wedge-shaped distal end and moves along the axial direction in accordance with an opening/closing operation of the opening/closing operation unit; wherein the treating unit (4, 1004) is rotatable around the axis in the extending direction in accordance with a rotating operation of the rotating operation unit, characterized in that one of the two pinching members comprises a conical wedge receiving portion (1213a, 1080, 1092) configured to receive the wedge member (1204, 1089a); and an open/close operation of the treating unit causes movement of at least the one of the two pinching members in the direction substantially orthogonal to planes of the planar portions comprising the wedge receiving portion (1213a, 1080, 1092) by moving the wedge member (1204, 1089a) in the axial direction of the insertion unit to push the wedge receiving portion (1213a, 1080, 1092) in accordance with the opening/closing operation of the opening/closing operation unit. an insertion unit (2, 1002); a treating unit (4, 1004) that is arranged at one end of the insertion unit (2, 1002) to be extended in an extending direction at a predetermined angle to the axial direction of the insertion unit (2, 1002); an operation unit (3, 1003) that is arranged at the other end of the insertion unit (2, 1002); a rotating operation unit that is arranged to the operation unit (3, 1003) to rotate the treating unit (4, 1004); and an opening/closing operation unit that is arranged to the operation unit (3, 1003) to open/close the treating unit (4, 1004), two pinching members (1035, 1037, 1084, 1089, 1212, 1212a, 1212b) that are provided at the treating unit (4, 1004), each of the two pinching members having a planar portion surface (1214a, 1216a, 1035b, 1037a, 1057a, 1084a, 1089a), wherein the planar portions surface (1214a, 1216a, 1035b, 1037a) of the two pinching members (1035, 1037, 1212) are configured to pinch a needle therebetween when the pinching members are in a closed state; a wedge member (1204, 1081a) that has a wedge-shaped distal end and moves along the axial direction in accordance with an opening/closing operation of the opening/closing operation unit; wherein the treating unit (4, 1004) is rotatable around the axis in the extending direction in accordance with a rotating operation of the rotating operation unit, characterized in that one of the two pinching members comprises a conical wedge receiving portion (1213a, 1080, 1092) configured to receive the wedge member (1204, 1089a); and an open/close operation of the treating unit causes movement of at least the one of the two pinching members in the direction substantially orthogonal to planes of the planar portions comprising the wedge receiving portion (1213a, 1080, 1092) by moving the wedge member (1204, 1089a) in the axial direction of the insertion unit to push the wedge receiving portion (1213a, 1080, 1092) in accordance with the opening/closing operation of the opening/closing operation unit.