A pushbutton switch includes a pushbutton for changing a switching mode of a tact switch provided on a switch holder fixedly disposed within a casing. The pushbutton includes a push operation portion disposed in a through hole provided in the casing and a collar that protrudes outwardly from the push operation portion and faces an inner face of the casing at the peripheral edge of the through hole. The pushbutton is connected to the switch holder and resiliently urged toward the side on which the collar gets closer to the inner face of the casing. Projections projecting toward the inner face of the casing are projectingly provided integrally at a plurality of positions spaced in the peripheral direction on an opposing face, of the collar of the pushbutton, that is opposed to the inner face of the casing. This prevents a freezing problem in the operation of a pushbutton.