A microswitch includes a contact chamber that accommodates a contact mechanism that opens and closes an electrical circuit; an enclosure that accommodates the contact chamber; and a pressing component that accepts a pressure external to the enclosure. The pressing component may include an insertion part that is inserted into an insertion hole in the contact chamber and acts on the contact mechanism, the insertion part receiving a pressure external thereto and moving from a first side that is outward of the enclosure to a second side that is inward of the enclosure. The pressing component may include a shielding part that shields the insertion hole from the contact chamber side, the shielding part being larger than the insertion hole in a direction orthogonal to an insertion direction to block the insertion hole.