The invention relates to a method for providing an alarm about a positioning fault in a self-moving device. A self-moving device is configured to autonomously move, based on positioning of the self-moving device, inside a working region defined on a map. The method includes: receiving positioning data from a satellite positioning system to locate the self-moving device; detecting whether a positioning fault occurs in the self-moving device; and in response to a detected positioning fault that occurs in the self-moving device, providing an alarm about the positioning fault.