A flexible button of a push switch includes a peripheral side wall having an opening at the bottom. A switch board is fitted in the opening of the peripheral side wall. A switch is provided on the switch board. A tubular case is fixed in place around the peripheral side wall. A stopper is disposed under the switch board, and latched on the inner face of the case. Filler fills the underside of the switch board, and fills at least an area that includes the entire peripheral length of the bottom periphery of the switch board and the bottom-end inner peripheral face of the peripheral side wall.