An object grasping device configured to grasp an outer peripheral surface of an object, the object grasping device comprising: an upper frame provided to have an inner peripheral surface shape corresponding to an outer peripheral surface of an upper portion of the object so as to surround the outer peripheral surface of the upper portion of the object in a grasping completion state in which the object grasping device grasps the outer peripheral surface of the object; a left lower frame provided to have an inner peripheral surface shape corresponding to an outer peripheral surface of a left lower portion of the object so as to surround the outer peripheral surface of the left lower portion of the object in the grasping completion state; and a right lower frame provided to have an inner peripheral surface shape corresponding to an outer peripheral surface of a right lower portion of the object so as to surround the outer peripheral surface of the right lower portion of the object in the grasping completion state, characterised by a left link member configured to link a left portion of the upper frame and a middle portion of the left lower frame by means of hinges each having a rotating axis defined in a forward/backward direction; and a right link member configured to link a right portion of the upper frame and a middle portion of the right lower frame by means of hinges each having a rotating axis defined in the forward/backward direction, wherein a grasping preparation state before the object is introduced between the left link member and the right link member is a state in which the left lower frame surrounds the outer peripheral surface of the left upper portion of the object and the right lower frame surrounds the outer peripheral surface of the right upper portion of the object, wherein the grasping completion state is a state in which the left lower frame is rotated counterclockwise based on the grasping preparation state and surrounds the outer peripheral surface of the left lower portion of the object and the right lower frame is rotated clockwise based on the grasping preparation state and surrounds the outer peripheral surface of the right lower portion of the object, wherein the left link member and the right link member are provided so that an interval between the left lower frame and the right lower frame forms a spacing gap through which the object passes in an intermediate grasping state in which the grasping preparation state is switched to the grasping completion state, and wherein when a pushing pressure is applied to the object grasping device in the grasping preparation state, the left lower frame and the right lower frame rotate and reach the grasping completion state via the intermediate grasping state in which the spacing gap is formed. an upper frame provided to have an inner peripheral surface shape corresponding to an outer peripheral surface of an upper portion of the object so as to surround the outer peripheral surface of the upper portion of the object in a grasping completion state in which the object grasping device grasps the outer peripheral surface of the object; a left lower frame provided to have an inner peripheral surface shape corresponding to an outer peripheral surface of a left lower portion of the object so as to surround the outer peripheral surface of the left lower portion of the object in the grasping completion state; and a right lower frame provided to have an inner peripheral surface shape corresponding to an outer peripheral surface of a right lower portion of the object so as to surround the outer peripheral surface of the right lower portion of the object in the grasping completion state, characterised by a left link member configured to link a left portion of the upper frame and a middle portion of the left lower frame by means of hinges each having a rotating axis defined in a forward/backward direction; and a right link member configured to link a right portion of the upper frame and a middle portion of the right lower frame by means of hinges each having a rotating axis defined in the forward/backward direction, wherein a grasping preparation state before the object is introduced between the left link member and the right link member is a state in which the left lower frame surrounds the outer peripheral surface of the left upper portion of the object and the right lower frame surrounds the outer peripheral surface of the right upper portion of the object, wherein the grasping completion state is a state in which the left lower frame is rotated counterclockwise based on the grasping preparation state and surrounds the outer peripheral surface of the left lower portion of the object and the right lower frame is rotated clockwise based on the grasping preparation state and surrounds the outer peripheral surface of the right lower portion of the object, wherein the left link member and the right link member are provided so that an interval between the left lower frame and the right lower frame forms a spacing gap through which the object passes in an intermediate grasping state in which the grasping preparation state is switched to the grasping completion state, and wherein when a pushing pressure is applied to the object grasping device in the grasping preparation state, the left lower frame and the right lower frame rotate and reach the grasping completion state via the intermediate grasping state in which the spacing gap is formed.