Humidifier

The utility model discloses a humidifier. The humidifier includes a housing for storing water, and the humidifier has a control circuit. The humidifier further comprises a sound wave detector installed on the shell, the sound wave detector is used for detecting the distance between the water surface in the shell and the sound wave detector, and the distance between the sound wave detector and the water surface is a. When a is smaller than a first preset threshold value, the control circuit is switched on; when a is greater than or equal to a first preset threshold value, the control circuit is disconnected. By means of the design, when the water storage amount in the shell is insufficient and water needs to be supplemented into the humidifier, the distance a between the sound wave detector and the water surface is larger than the first preset threshold value, the control circuit of the humidifier is disconnected, and then the humidifier automatically stops. By arranging the sound wave detector, a floating pie