The electronic device and a preventing data loss method adapted for an electronic device are disclosed. The electronic device includes a storage unit to store an application. The method includes the steps: running an application in response to user input. Detecting the user input in real time and starting to time when the user input is not detected, and evaluating whether the period timed reaches a predetermined time period. If the predetermined time period is elapsed, suspending the application and detecting an electric energy of a battery providing power to the electronic device; evaluating whether the electric energy of the battery reaches a preset value. If the electric energy of the battery reaches the preset value, making a backup of process data associated with the suspended application in the storage unit.