A low voltage threshold adjusting method is provided and includes the following steps: detecting whether a present voltage is lower than a low voltage threshold; detecting whether a present current exceeds a preset current threshold in response to that the present voltage is lower than the low voltage threshold; detecting whether a present temperature exceeds a preset temperature in response to that the present current exceeds the preset current threshold; checking whether a current state of charge (SOC) is higher than a preset SOC in response to that the present temperature does not exceed the preset temperature; and decreasing the low voltage threshold in response to that the current SOC is higher than the preset SOC.