PURPOSE: To provide a structure of waterproof sounder which is high in waterproof and acoustic effects, can be produced by simple procedure, is highly operable, and allows a user to use it merrily.

CONSTITUTION: A structure of waterproof sounder 1 consists of a circuit board 8 in which a sound generating part 9 is built, a resonance cylinder attached to the sound generating part 9, a basket 2 which covers the circuit board 8 and resonance cylinder and has an opening at a prescribed position, a battery pocket 12 forming a cavity below the basket 2, and a supporting table 4 which supports the basket 2 in such a way that they are assembled and dissembled freely, where the upper end of the resonance cylinder is linked to the opening of the basket 2 via a thin, waterproof sheet, and one end of an assembling/ dissembling mechanism 3 is formed below the basket 2 and the other end on the supporting table 4.