A seal member (7) is provided between a combustor disposed around a rotor axis and a vane disposed on the downstream side in an axial direction and defining a part of a combustion gas flow passage (Pg) through which combustion gas (G) flows, and seals a gap between the combustor and the vane. The seal member (7) has: an end face (71a) that faces the downstream side in the axial direction so as to face a lateral end face (461) of the vane facing the upstream side in the axial direction; cooling channels (80) through which cooling air is discharged from a plurality of openings (80a) provided in the end face (71a) in an array in a circumferential direction based on the rotor axis; and a clearance forming portion (71b) that protrudes further toward the downstream side in the axial direction than the end face (71a) in which the openings are formed.