A keyswitch includes a cap, a support structure, a first magnet, and a baseplate having a bending arm protruding from the baseplate and a support rib extending horizontally to form a receiving space with the bending arm. The support structure includes a first support member pivoted to the baseplate and against the cap and a magnetic permeable plate extending from the first support member and being above the receiving space. The first magnet is inserted into the receiving space to be supported by the support rib and be pressed by the bending arm. When the cap is pressed to make the magnetic permeable plate away from the first magnet as the first support member rotates, the cap moves to a pressed position. When the cap is released, a magnetic attraction force between the magnetic permeable plate and the first magnet drives the magnetic permeable plate to approach the first magnet.