A battery overheating protection circuit includes a thermal resistor samples the temperature of the battery and converts the temperature into a temperature voltage, a comparison circuit compares the temperature voltage with a reference voltage for judging whether the temperature of the battery is higher than the maximum reference temperatures temperature or not. If yes, the comparison circuit outputs a protection signal to drive a charging module to stop charging the battery in the charging process, and to cut off the conducting path to draw power from the battery in the discharging process. The present invention sets two different maximum reference temperatures during charging process and discharging process by a reference voltage module, which makes the maximum allowable discharging temperature is higher than the maximum allowable charging temperature.