Abstract: In a tact switch in which pressing operation on an operating portion of an actuator member will cause the forward end portion of the actuator member to be pushed toward the bottom surface of a housing while being guided by an inclined surface so that the forward end portion (flexible portion) of the actuator member is flexed to press down on the marginal regions of a movable contact piece whereby the curved section of the movable contact piece is flipped over, a cam defining the inclined surface is provided separately from the housing. The movable contact piece, the actuator member, the cam and a top lid may be assembled together simply by stacking them sequentially from above onto the housing.