A loudspeaker system includes a loudspeaker enclosure having an inside space, a loudspeaker provided on the loudspeaker enclosure, a first diaphragm which has one of ends fixed to a surface of the loudspeaker enclosure and the other end, a second diaphragm which has one of ends fixed to the surface of the loudspeaker enclosure and the other end, a coupling portion having an elasticity, and coupling the other end of the first diaphragm to the other end of the second diaphragm, an opening structure provided in the surface of the loudspeaker enclosure, and a sealing member provided to a portion among the first and second diaphragms, the coupling portion and an edge part of the opening structure, and closing the inside space to hold an airtightness of the loudspeaker enclosure in a state that the first and second diaphragms can be vibrated.