A turbine blade comprising: a blade body that is arranged to be mounted on a rotor body so as to extend outward from the rotor body in a radial direction of the rotor body; and a tip shroud that is fixed to the outside of the blade body in the radial direction, wherein a cooling passage which extends in the radial direction of the rotor body and in which a cooling medium can circulate is formed in the blade body, and the tip shroud includes: a shroud body where a recess opened to the outside in the radial direction and communicating with the cooling passage is formed on an outer peripheral end face of the shroud body, characterised in that it comprises a plug that includes a plurality of plug pieces (71,72;70a-c) closing an opening of the recess in cooperation with each other by being inserted into mounting grooves formed on side surfaces of the recess wherein the outer peripheral end face of the shroud body has a first main surface, wherein the shroud body includes a plug insertion port for inserting the plug pieces (71,72;70a-c) into the mounting grooves on at least one end side in the longitudinal direction of the recess, wherein a portion of a front side in the longitudinal direction of the recess forms an insertion surface which is raised outwardly from the first main surface in the radial direction so as to surround the recess from both sides in the lateral direction and a rear side in the longitudinal direction of the recess, wherein the positions of the mounting grooves in the radial direction are substantially the same as the position of the insertion surface in the radial direction, and wherein an area of the outer peripheral end face of the shroud body which includes edge portions of the recess except for the front side in the longitudinal direction forms a second main surface which is raised from the first main surface and the insertion surface outwardly in the radial direction. a blade body that is arranged to be mounted on a rotor body so as to extend outward from the rotor body in a radial direction of the rotor body; and a tip shroud that is fixed to the outside of the blade body in the radial direction, wherein a cooling passage which extends in the radial direction of the rotor body and in which a cooling medium can circulate is formed in the blade body, and the tip shroud includes: a shroud body where a recess opened to the outside in the radial direction and communicating with the cooling passage is formed on an outer peripheral end face of the shroud body, characterised in that it comprises a plug that includes a plurality of plug pieces (71,72;70a-c) closing an opening of the recess in cooperation with each other by being inserted into mounting grooves formed on side surfaces of the recess wherein the outer peripheral end face of the shroud body has a first main surface, wherein the shroud body includes a plug insertion port for inserting the plug pieces (71,72;70a-c) into the mounting grooves on at least one end side in the longitudinal direction of the recess, wherein a portion of a front side in the longitudinal direction of the recess forms an insertion surface which is raised outwardly from the first main surface in the radial direction so as to surround the recess from both sides in the lateral direction and a rear side in the longitudinal direction of the recess, wherein the positions of the mounting grooves in the radial direction are substantially the same as the position of the insertion surface in the radial direction, and wherein an area of the outer peripheral end face of the shroud body which includes edge portions of the recess except for the front side in the longitudinal direction forms a second main surface which is raised from the first main surface and the insertion surface outwardly in the radial direction. a shroud body where a recess opened to the outside in the radial direction and communicating with the cooling passage is formed on an outer peripheral end face of the shroud body, characterised in that it comprises a plug that includes a plurality of plug pieces (71,72;70a-c) closing an opening of the recess in cooperation with each other by being inserted into mounting grooves formed on side surfaces of the recess wherein the outer peripheral end face of the shroud body has a first main surface, wherein the shroud body includes a plug insertion port for inserting the plug pieces (71,72;70a-c) into the mounting grooves on at least one end side in the longitudinal direction of the recess, wherein a portion of a front side in the longitudinal direction of the recess forms an insertion surface which is raised outwardly from the first main surface in the radial direction so as to surround the recess from both sides in the lateral direction and a rear side in the longitudinal direction of the recess, wherein the positions of the mounting grooves in the radial direction are substantially the same as the position of the insertion surface in the radial direction, and wherein an area of the outer peripheral end face of the shroud body which includes edge portions of the recess except for the front side in the longitudinal direction forms a second main surface which is raised from the first main surface and the insertion surface outwardly in the radial direction.