Embodiments of the present application disclose a method for saving a running log, including: when a running exception occurs in an operating system, configuring that a random access memory adapted to record a running log of the operating system works in a self-refresh mode; performing reset on an application processor of the operating system and keeping a power management unit working normally, where the power management unit is adapted to manage power of the application processor and the random access memory; acquiring the running log of the operating system from the random access memory and saving the running log of the operating system, after reset of the application processor is completed. The embodiments of the present application further disclose a device. By adopting the present application, it can be ensured that a log is saved completely during a preset process of the system.