A high-frequency treatment tool (1; 61) comprising: a longitudinal insertion part; a manipulation part which is coupled to the insertion part; a treatment part (10; 65) which is provided at a distal end portion of the insertion part, whereby the treatment part (10; 65) includes: a cover member which is mounted on the distal end portion of the insertion part; a first treatment member which is rotatably supported within the cover member, which is configured to rotate about a shaft, and to which a high-frequency current is capable of being applied; and a second member (12; 62) which is configured to rotate about the shaft, the second member (12; 62) including a rod-shaped main body (12a; 62a), and the manipulation part includes: a first drive shaft that is connected to the first treatment member by a first transmission member and rotatably driven to rotate the first treatment member; and a second drive shaft that is connected to the second member (12; 62) by a second transmission member and rotatably driven to rotate the second member (12; 62), characterized in that the second member is rotatably supported within the cover member and in that the second member includes an insulating chip (12b; 62b) mounted on a distal end of the main body (12a; 62a). a longitudinal insertion part; a manipulation part which is coupled to the insertion part; a treatment part (10; 65) which is provided at a distal end portion of the insertion part, whereby the treatment part (10; 65) includes: a cover member which is mounted on the distal end portion of the insertion part; a first treatment member which is rotatably supported within the cover member, which is configured to rotate about a shaft, and to which a high-frequency current is capable of being applied; and a second member (12; 62) which is configured to rotate about the shaft, the second member (12; 62) including a rod-shaped main body (12a; 62a), and a cover member which is mounted on the distal end portion of the insertion part; a first treatment member which is rotatably supported within the cover member, which is configured to rotate about a shaft, and to which a high-frequency current is capable of being applied; and a second member (12; 62) which is configured to rotate about the shaft, the second member (12; 62) including a rod-shaped main body (12a; 62a), and the manipulation part includes: a first drive shaft that is connected to the first treatment member by a first transmission member and rotatably driven to rotate the first treatment member; and a second drive shaft that is connected to the second member (12; 62) by a second transmission member and rotatably driven to rotate the second member (12; 62), characterized in that the second member is rotatably supported within the cover member and in that the second member includes an insulating chip (12b; 62b) mounted on a distal end of the main body (12a; 62a). a first drive shaft that is connected to the first treatment member by a first transmission member and rotatably driven to rotate the first treatment member; and a second drive shaft that is connected to the second member (12; 62) by a second transmission member and rotatably driven to rotate the second member (12; 62), characterized in that the second member is rotatably supported within the cover member and in that the second member includes an insulating chip (12b; 62b) mounted on a distal end of the main body (12a; 62a).