The present disclosure provides an underwater speaker. The underwater speaker includes an outer shell, with a circuit board arranged inside, a speaker, and a lampshade with a first opening at the top. The speaker is electrically connected to the circuit board. The luminescent body is arranged on the circuit board. The luminescent body is oriented towards the interior of the lampshade, and a graphic mapping unit is formed on the lampshade. This embodiment uses the speaker to play audio and achieve the function of an underwater speaker. When the luminescent body emits light, the light can be mapped onto the water. This improves the multiplicity and effect of light and shadow, and meets users' needs for complex and multi-element light and shadow effects.