The present invention provides a method for dynamically adjusting battery undervoltage protection, including: real time acquiring a current operation environment temperature value of a battery; real time selecting a preset undervoltage protection voltage and a preset undervoltage protection delay time according to the temperature value; real time determining whether an output voltage of the battery is less than the undervoltage protection voltage; if yes, then: determining whether a time interval when the output voltage of the battery is less than the undervoltage protection voltage satisfies the undervoltage protection delay time, if yes, then: enabling the battery undervoltage protection. The present invention is capable of performing a flexible battery undervoltage protection according to a current operation environment temperature of the battery. The present invention also provides a system for dynamically adjusting battery undervoltage protection.