The invention aims to provide an automatic energy-saving descaling embedded heater. The automatic energy-saving descaling embedded heater comprises a thermal insulation layer, a heating tank, a heating ring embedded groove, a heating ring, a heating ring cover, a temperature limiter, a descaling impeller, push vanes, a descaling impeller fixing shaft, a reverse-L-shaped water inlet pipe, a water outlet pipe and an overflow pipe. The automatic energy-saving descaling embedded heater has the advantages that the heating ring is arranged inside the embedded groove of the heating tank and can transmit more than 90% of heat into the heating tank, the heating speed is increased, and the energy is saved; the descaling impeller rotates along with the inlet water push force so as to descale the heating ring embedded groove, and the heating effect is guaranteed; water flows out of the heater after the overflow pipe is full, so that pressure in the heating tank is absent to achieve protecting effect on the heating tank, personal safety is guaranteed, and the thermal insulation layer is added so that the thermal insulation time and the service life of the heater are prolonged.