The invention provides an automatic protection control circuit for a ground resistor, and the automatic protection control circuit is applied to protector for the ground resistor in a power system. The automatic protection control circuit is used for starting a heat dissipation circuit of the ground resistor when a neutral point voltage in a measured power distribution system reaches a preset voltage threshold value, or the operating temperature of the ground resistor reaches a first preset temperature threshold value, and cutting off a tripping circuit of the ground resistor when the operating temperature of the measured ground resistor reaches a second preset temperature threshold value. According to the automatic protection control circuit, the reliable operation of the ground resistor for two hours or more after the power distribution system is subjected to single-phase earth fault can be ensured.