The invention relates to an underwater sounding device. A pressure induction triggered sounding device suitable for underwater includes a sounding device, a controller, a first pressure sensor, a second pressure sensor, and a flexible liquid storage bag. The flexible liquid storage bag is filled with liquid. The first pressure sensor is arranged in the flexible liquid storage bag. The second pressure sensor is used for detecting the water pressure outside the flexible liquid storage bag. When the difference obtained by subtracting the pressure detected by the second pressure sensor from the pressure detected by the first pressure sensor is greater than a preset value, the controller makes the sounding device make sound. The invention provides a pressure induction triggered sounding devicesuitable for underwater. The problem that the existing sounding device can be controlled only through direct action on the switch is solved.