An electro-surgical device (12; 12a; 12b; 12c) for joining living tissues, comprising: a pair of holding members (52a, 52b; 242; 244) each having a holding member main body with a holding face (54a, 54b; 80a, 80b; 116a, 116b; 134a; 138a, 138b; 142a, 142b; 144a; 252a, 284a; 274, 288) configured to grip and hold the living tissues; a joining treatment portion (54a, 54b; 134a; 142a, 142b; 274, 288) arranged in at least one of the holding faces to join the living tissues held between the holding faces by energy supplied from an energy source; a pair of base members (64a, 64b) each provided on a base end side of the holding member main body (62a, 62b), and a fluid feed portion (56a, 56b; 136a; 152a, 152b; 170a, 170b; 274b, 288b; 274c, 288c) provided on the holding face or the joining treatment portion, and being able to feed a fluid between the holding faces; suction means configured to suck fluid from the space formed between the holding members through a fluid flow channel (78a, 120, 140a, 170a, 264) formed at the base members (64a, 64b) such that the fluid is discharged through the base members (64a, 64b), the electrosurgical device further comprising, either an annular recess (76a; 117; 276) provided on the holding faces /54a, 54b) or the joining treatment portion outside the fluid feed portion (56a, 56b) of the holding face or the joining treatment portion, or barrier portions (116a, 116b) formed inside the edge of the main body (62a, 62b) of the first and second holding members (52a, 52b) such that when the holding members are closed the barrier portions (116a, 116b) are mutually brought into contact, but a space is formed between the first and second joining treatment portions (54a, 54b), or a recess formed inside a barrier portion, wherein said barrier portion is formed in the edge of the main body of the first and second holding member (52a, 54b) with a plurality of fluid discharge holes passing through the first and second holding member, wherein the annular recess (76a, 117), or the barrier portions (116a, 116b), or both prevent the fluid fed from the fluid fed portion (56a, 56b) from leaking out of the holding members when the holding members are closed. a pair of holding members (52a, 52b; 242; 244) each having a holding member main body with a holding face (54a, 54b; 80a, 80b; 116a, 116b; 134a; 138a, 138b; 142a, 142b; 144a; 252a, 284a; 274, 288) configured to grip and hold the living tissues; a joining treatment portion (54a, 54b; 134a; 142a, 142b; 274, 288) arranged in at least one of the holding faces to join the living tissues held between the holding faces by energy supplied from an energy source; a pair of base members (64a, 64b) each provided on a base end side of the holding member main body (62a, 62b), and a fluid feed portion (56a, 56b; 136a; 152a, 152b; 170a, 170b; 274b, 288b; 274c, 288c) provided on the holding face or the joining treatment portion, and being able to feed a fluid between the holding faces; suction means configured to suck fluid from the space formed between the holding members through a fluid flow channel (78a, 120, 140a, 170a, 264) formed at the base members (64a, 64b) such that the fluid is discharged through the base members (64a, 64b), the electrosurgical device further comprising, either an annular recess (76a; 117; 276) provided on the holding faces /54a, 54b) or the joining treatment portion outside the fluid feed portion (56a, 56b) of the holding face or the joining treatment portion, or barrier portions (116a, 116b) formed inside the edge of the main body (62a, 62b) of the first and second holding members (52a, 52b) such that when the holding members are closed the barrier portions (116a, 116b) are mutually brought into contact, but a space is formed between the first and second joining treatment portions (54a, 54b), or a recess formed inside a barrier portion, wherein said barrier portion is formed in the edge of the main body of the first and second holding member (52a, 54b) with a plurality of fluid discharge holes passing through the first and second holding member, wherein the annular recess (76a, 117), or the barrier portions (116a, 116b), or both prevent the fluid fed from the fluid fed portion (56a, 56b) from leaking out of the holding members when the holding members are closed.