A resonating speaker comprises: an upper cover, an upper magnet, a positioning member, a magnetostrictive member, a coil, a lower magnet, a lower cover and a sound-transmitting member. The upper magnet, the positioning member, the magnetostrictive member, and the lower magnet are disposed in the upper cover. And then the connecting portion of the lower cover is connected to that of the upper cover, so that the lower magnet, the magnetostrictive member, and the upper magnet are pressed onto the upper cover by the upper cover, while leaving resonance space between the upper and lower covers. The vibration-transmitting member is fixed to the lower cover. Hence, the resonating speaker is small and easy to carry, and can play sound simply by puffing it on a sound-transmitting medium.