A sealing device for sealing a gap between a rotational shaft and a housing for the rotational shaft, including: a first sealing member adapted to be mounted on the housing, an outer peripheral surface of the rotational shaft being in slidable contact with the first sealing member when in use; and a second sealing member adapted to be mounted on the housing, the outer peripheral surface of the rotational shaft being in slidable contact with the second sealing member when in use, the first sealing member comprising multiple first hooks projecting from a surface thereof facing the second sealing member, each first hook comprising a proximal portion and a distal portion bent from the proximal portion and oriented in a radial direction of the sealing device, the second sealing member comprising multiple second hooks projecting from a surface thereof facing the first sealing member, each second hook comprising a proximal portion and a distal portion bent from the proximal portion and oriented in a radial direction of the sealing device, the distal portion of each second hook being hooked on the distal portion of one of the first hooks for restricting movement of the second sealing member away from the first sealing member in an axial direction of the sealing device, characterized in that: the first sealing member comprises multiple first stoppers projecting from the surface thereof facing the second sealing member; the second sealing member comprises multiple second stoppers projecting from the surface thereof facing the first sealing member; a distal portion of each second stopper is configured to be in contact with a distal portion of one of the first stoppers for restricting movement of the second sealing member toward the first sealing member in the axial direction; and the sealing device is configured such that, when the distal portions of the second stoppers are in contact with the distal portions of the first stoppers, there are clearances between the first hooks and the second hooks in such a manner that the first hooks are not in contact with the second sealing member, and the second hooks are not in contact with the first sealing member. a first sealing member adapted to be mounted on the housing, an outer peripheral surface of the rotational shaft being in slidable contact with the first sealing member when in use; and a second sealing member adapted to be mounted on the housing, the outer peripheral surface of the rotational shaft being in slidable contact with the second sealing member when in use, the first sealing member comprising multiple first hooks projecting from a surface thereof facing the second sealing member, each first hook comprising a proximal portion and a distal portion bent from the proximal portion and oriented in a radial direction of the sealing device, the second sealing member comprising multiple second hooks projecting from a surface thereof facing the first sealing member, each second hook comprising a proximal portion and a distal portion bent from the proximal portion and oriented in a radial direction of the sealing device, the distal portion of each second hook being hooked on the distal portion of one of the first hooks for restricting movement of the second sealing member away from the first sealing member in an axial direction of the sealing device, characterized in that: the first sealing member comprises multiple first stoppers projecting from the surface thereof facing the second sealing member; the second sealing member comprises multiple second stoppers projecting from the surface thereof facing the first sealing member; a distal portion of each second stopper is configured to be in contact with a distal portion of one of the first stoppers for restricting movement of the second sealing member toward the first sealing member in the axial direction; and the sealing device is configured such that, when the distal portions of the second stoppers are in contact with the distal portions of the first stoppers, there are clearances between the first hooks and the second hooks in such a manner that the first hooks are not in contact with the second sealing member, and the second hooks are not in contact with the first sealing member. the first sealing member comprises multiple first stoppers projecting from the surface thereof facing the second sealing member; the second sealing member comprises multiple second stoppers projecting from the surface thereof facing the first sealing member; a distal portion of each second stopper is configured to be in contact with a distal portion of one of the first stoppers for restricting movement of the second sealing member toward the first sealing member in the axial direction; and the sealing device is configured such that, when the distal portions of the second stoppers are in contact with the distal portions of the first stoppers, there are clearances between the first hooks and the second hooks in such a manner that the first hooks are not in contact with the second sealing member, and the second hooks are not in contact with the first sealing member.