A pallet clamp for fixing a pallet to a table, with the pallet positioned on the table, the pallet clamp comprising: a clamp receiver adapted to be on a back surface of the pallet; a clamp adapted to be on a mounting surface of the table, the clamp facing the clamp receiver; and a press-fitted portion at which the clamp receiver and the clamp are press-fitted to each other in a direction perpendicular to the mounting surface by a biasing means; wherein the clamp receiver has, at the press-fitted portion, an abutted surface having serrations; the clamp has, at the press-fitted portion, an abutting surface having serrations, the abutting surface coming into tight contact with the abutted surface; characterized in that: one of the clamp receiver or the clamp has both of a pressed surface and a counter pressed surface which face in directions along alignment and extension of ridges and grooves of the serrations, or one of the clamp receiver or the clamp has the pressed surface and the other has the counter pressed surface, and the biasing means press-fits the clamp receiver and the clamp to each other so that the abutting surface and the abutted surface come into tight contact with each other, which causes the pressed surface and the counter pressed surface to be pressed in opposite directions, the pallet clamp further includes a key member interposed between the clamp receiver and the clamp where the clamp receiver is fixed to the clamp via a fastening bolt, wherein the clamp receiver has a keyway in the abutted surface, the keyway traversing the serrations, the clamp has a support groove in the abutting surface, the support groove traversing the serrations and facing the keyway, the key member includes a key to be fitted into the keyway, and a support to be fitted into the support groove, the support is fitted into the support groove to be in an unremovable state, and the key is fitted into the keyway with a gap interposed therebetween, and the keyway tilts with respect to the key when the key is fitted to, but not press-fitted to, the keyway, and the abutting surface and the abutted surface that have come into tight contact with each other cause the key to press the pressed surface and the counter pressed surface. a clamp receiver adapted to be on a back surface of the pallet; a clamp adapted to be on a mounting surface of the table, the clamp facing the clamp receiver; and a press-fitted portion at which the clamp receiver and the clamp are press-fitted to each other in a direction perpendicular to the mounting surface by a biasing means; wherein the clamp receiver has, at the press-fitted portion, an abutted surface having serrations; the clamp has, at the press-fitted portion, an abutting surface having serrations, the abutting surface coming into tight contact with the abutted surface; characterized in that: one of the clamp receiver or the clamp has both of a pressed surface and a counter pressed surface which face in directions along alignment and extension of ridges and grooves of the serrations, or one of the clamp receiver or the clamp has the pressed surface and the other has the counter pressed surface, and the biasing means press-fits the clamp receiver and the clamp to each other so that the abutting surface and the abutted surface come into tight contact with each other, which causes the pressed surface and the counter pressed surface to be pressed in opposite directions, the pallet clamp further includes a key member interposed between the clamp receiver and the clamp where the clamp receiver is fixed to the clamp via a fastening bolt, the clamp receiver has a keyway in the abutted surface, the keyway traversing the serrations, the clamp has a support groove in the abutting surface, the support groove traversing the serrations and facing the keyway, the key member includes a key to be fitted into the keyway, and a support to be fitted into the support groove, the support is fitted into the support groove to be in an unremovable state, and the key is fitted into the keyway with a gap interposed therebetween, and the keyway tilts with respect to the key when the key is fitted to, but not press-fitted to, the keyway, and the abutting surface and the abutted surface that have come into tight contact with each other cause the key to press the pressed surface and the counter pressed surface.