An impeller cover comprising: a machinable abradable seal section including a shroud surface adapted to be facing an outer peripheral surface of an impeller rotating about an axis and providing sealing between the outer peripheral surface and the shroud surface ; a cover main body covering the impeller from an outside and including a seal housing section in which the abradable seal section is housed; and a filling material interposed between the abradable seal section and the cover main body , wherein the seal housing section has a fitting inner peripheral surface extending along an axis for an outer peripheral surface of the abradable seal section to be fitted to the fitting inner peripheral surface and a reference surface positioning the abradable seal section in an axial direction by abutting against the abradable seal section from one side in the axial direction, wherein the seal housing section has a capturing unit capturing a surplus of the filling material by forming a gap in at least a part of a space between the abradable seal section and the seal housing section , wherein a first groove portion (R1) recessed radially outwards and extending in a peripheral direction is formed in the fitting inner peripheral surface, and wherein a second groove portion (R2) extending in the peripheral direction in a region facing the first groove portion (R1) and having an axial dimension smaller than an axial dimension of the first groove portion (R1) is formed in the outer peripheral surface of the abradable seal section , characterized in that the capturing unit is a radially extending recessed groove formed in at least a part of an end face on the one side in the axial direction of the abradable seal section , wherein an end portion of the recessed groove on the outer side in the radial direction is connected to the first groove portion (R1). a machinable abradable seal section including a shroud surface adapted to be facing an outer peripheral surface of an impeller rotating about an axis and providing sealing between the outer peripheral surface and the shroud surface ; a cover main body covering the impeller from an outside and including a seal housing section in which the abradable seal section is housed; and a filling material interposed between the abradable seal section and the cover main body , wherein the seal housing section has a fitting inner peripheral surface extending along an axis for an outer peripheral surface of the abradable seal section to be fitted to the fitting inner peripheral surface and a reference surface positioning the abradable seal section in an axial direction by abutting against the abradable seal section from one side in the axial direction, wherein the seal housing section has a capturing unit capturing a surplus of the filling material by forming a gap in at least a part of a space between the abradable seal section and the seal housing section , wherein a first groove portion (R1) recessed radially outwards and extending in a peripheral direction is formed in the fitting inner peripheral surface, and wherein a second groove portion (R2) extending in the peripheral direction in a region facing the first groove portion (R1) and having an axial dimension smaller than an axial dimension of the first groove portion (R1) is formed in the outer peripheral surface of the abradable seal section , characterized in that the capturing unit is a radially extending recessed groove formed in at least a part of an end face on the one side in the axial direction of the abradable seal section , wherein an end portion of the recessed groove on the outer side in the radial direction is connected to the first groove portion (R1). <EOS>