The invention provides a half-voltage circuit protection method and a mobile terminal. The method comprising: charging a charging capacitor by a first current, the current value of the first current being less than the rated operational current of a half-voltage circuit; acquiring the temperature value of the charging capacitor in the working state; determining the difference between the temperature value of the charging capacitor in the working state and the temperature value of the charging capacitor in the non-working state as the temperature rise value of the charging capacitor; determining a current value corresponding to the temperature rise value; when the current value corresponding to the temperature rise value is less than or equal to the rated operational current of the half-voltage circuit, adjusting the first current to the rated operational current; and when the current value corresponding to the temperature rise value is greater than the rated operational current of the half-voltage circuit, reducing the current value of the first current. The temperature rise value of the charging capacitor in the half-voltage circuit is used as the detection basis for judging whether the charging capacitor is in the open circuit failure, the open circuit state of the charging capacitor can be detected in real time, the state of the half-voltage circuit is enabled to be safe and controllable, and the charging effect of the mobile terminal is ensured.