Electrothermal water boiler for preventing dry burn

The utility model relates to an electrothermal water boiler, particularly an electrothermal water boiler for preventing dry burn, which comprises an inner bag, a water pump and a control circuit which are arranged on the bottom of the inner bag, wherein the lower part of the inner bag is provided with a water outlet which is connected with a pumping opening of the water pump. A drain outlet of the water pump is connected with a water outlet of the electrothermal water boiler. The electrothermal water boiler is also provided with a transparent pipe, wherein the lower end of the transparent pipe is communicated with the lower part of the inner bag and the upper end is conducted with the upper part of the inner bag. A float, an upper limiting device and a lower limiting device which are used for limiting the movement of the float are arranged in the transparent pipe. A light controlling device is arranged on the transparent pipe at a position of designated water level and is composed of a light emitting head and a receiving head which are respectively arranged on both corresponding sides of the float. The light controlling device is electrically connected with the control circuit, and the transparent pipe for displaying the water level is singly connected with the inner bag so that the defects that the dirt of the bottom of the inner bag is easily sucked into the transparent pipe because of the connection between the transparent pipe for displaying the water level and the drain outlet of the water pump and the prevention of the dry burn is influenced are avoided.