A treatment system (10; 210; 410) which is adapted to exert energy to a living tissue (L T) to treat the living tissue, comprising: a pair of holding members (36a, 36b; 262, 264; 442, 444) which are adapted to hold the living tissue therebetween, at least one of the holding members being configured to relatively move with respect to the other holding member and respectively include holding faces (272b, 276b, 442a, 444a) opposed to each other to hold the living tissue 1; 1 [18, [124, 214]. a high-frequency energy output section (52a, 52b, 72; 266, 270, 292; 472, 486, 292) which is provided on at least one of the holding faces of the holding members, which comes in contact with the living tissue (L T) and which is adapted to exert high-frequency energy to the living tissue to denature the living tissue and which is adapted to collect the biological information (Z, Δθ, T) of the living tissue held between the holding members; a heat generation element (54, 74; 268, 294; 474, 294) which is provided on at least one of the holding members and a back surface of the high-frequency energy output section 2, and which is adapted to apply heat to the living tissue held between the holding members, the heat generation element not being in contact with the living tissue and being configured to generate the heat owing to the supply of the energy and to conduct the heat from the heat generation element through the high-frequency energy output section (52a, 52b; 226, 270; 472, 486) to the living tissue (L T) 3, thereby denaturing the living tissue; and 2 See [17, 100, 147, 156, 242, 266] in addition to paragraph with respect to Figs. 12 and 18. 3. a control section (92, 102; 290) which is adapted to control the output of the energy to the high-frequency energy output section and the heat generation element based on the biological information collected by the high-frequency energy output section and which is able to switch, based on the biological information (Z, Δθ, T) of the living tissue (L T), between a treatment using the high-frequency energy due to the high-frequency energy output section (52a, 52b, 72; 266, 270, 292; 472, 486, 292) and a treatment using the heat energy due to the heat generation element (54, 74; 268, 294; 474, 294). a pair of holding members (36a, 36b; 262, 264; 442, 444) which are adapted to hold the living tissue therebetween, at least one of the holding members being configured to relatively move with respect to the other holding member and respectively include holding faces (272b, 276b, 442a, 444a) opposed to each other to hold the living tissue 1; 1 [18, [124, 214]. a high-frequency energy output section (52a, 52b, 72; 266, 270, 292; 472, 486, 292) which is provided on at least one of the holding faces of the holding members, which comes in contact with the living tissue (L T) and which is adapted to exert high-frequency energy to the living tissue to denature the living tissue and which is adapted to collect the biological information (Z, Δθ, T) of the living tissue held between the holding members; a heat generation element (54, 74; 268, 294; 474, 294) which is provided on at least one of the holding members and a back surface of the high-frequency energy output section 2, and which is adapted to apply heat to the living tissue held between the holding members, the heat generation element not being in contact with the living tissue and being configured to generate the heat owing to the supply of the energy and to conduct the heat from the heat generation element through the high-frequency energy output section (52a, 52b; 226, 270; 472, 486) to the living tissue (L T) 3, thereby denaturing the living tissue; and 2 See [17, 100, 147, 156, 242, 266] in addition to paragraph with respect to Figs. 12 and 18. 3. a control section (92, 102; 290) which is adapted to control the output of the energy to the high-frequency energy output section and the heat generation element based on the biological information collected by the high-frequency energy output section and which is able to switch, based on the biological information (Z, Δθ, T) of the living tissue (L T), between a treatment using the high-frequency energy due to the high-frequency energy output section (52a, 52b, 72; 266, 270, 292; 472, 486, 292) and a treatment using the heat energy due to the heat generation element (54, 74; 268, 294; 474, 294).