An axial seal structure in which multiple thin sheet seal pieces are arranged within an annular space between the outer peripheral side of a rotating shaft and a casing surrounding the periphery of the rotating shaft with minute gaps from each other in the circumferential direction such that their respective thickness direction is directed towards the circumferential direction of the rotating shaft, radial inner ends of the multiple thin sheet seal pieces being formed at free ends, and being configured to float from the outer peripheral surface of the rotating shaft by a dynamic pressure effect produced by the rotation of the rotating shaft when the rotating shaft rotates, while being in contact with an outer peripheral surface of the rotating shaft while the rotating shaft is not rotating, and radial outer ends of the multiple thin sheet seal pieces being coupled together, and divide the annular space into a high-pressure-side region and a low-pressure-side region in the axial direction of the rotating shaft, the axial seal structure comprising: high-pressure-side regulating device (30, 30x) that is arranged within the annular space and regulates the flow of a fluid from the high pressure side to the multiple thin sheet seal pieces along the high pressure side of the multiple thin sheet seal pieces and along the outer periphery of the rotating shaft, wherein the high-pressure-side regulating device has flexible multiple wires that are densely arranged in the circumferential direction of the rotating shaft, wherein respective longitudinal directions of the multiple wires face a direction having a radial component of the rotating shaft, wherein tips that are respective radial inner ends of the multiple wires form free ends, and are brought into close proximity to or into contact with the outer peripheral surface of the rotating shaft, and wherein base ends that are respective radial outer ends of the multiple wires are coupled together so that the wires that are adjacent to each other in the circumferential direction come into contact with each other at least partially in the longitudinal directions. high-pressure-side regulating device (30, 30x) that is arranged within the annular space and regulates the flow of a fluid from the high pressure side to the multiple thin sheet seal pieces along the high pressure side of the multiple thin sheet seal pieces and along the outer periphery of the rotating shaft, wherein the high-pressure-side regulating device has flexible multiple wires that are densely arranged in the circumferential direction of the rotating shaft, wherein respective longitudinal directions of the multiple wires face a direction having a radial component of the rotating shaft, wherein tips that are respective radial inner ends of the multiple wires form free ends, and are brought into close proximity to or into contact with the outer peripheral surface of the rotating shaft, and wherein base ends that are respective radial outer ends of the multiple wires are coupled together so that the wires that are adjacent to each other in the circumferential direction come into contact with each other at least partially in the longitudinal directions.