Automatic water level detection device

The invention provides an automatic water level detection device. The automatic water level detection device comprises a laser emitting unit, a laser receiving unit, a circuit interface and a transparent water pipe, the laser emitting unit and the laser receiving unit are located on the two sides of the non-center-line position of the cross section of the transparent water pipe respectively. When the water level in the transparent water pipe does not reach the device installation position, the laser emitted by the laser emitting unit reaches the laser receiving unit after passing through the transparent water pipe. When the laser receiving unit receives the laser, the signal output end P2 is at a low level and indicates that the water level does not reach the device mounting position. When the water level reaches or is higher than the installation position of the device, the laser is emitted into the water in the transparent water pipe in a non-vertical mode, and the laser is refracted and deviates from the l