An anti-lost notification method and an anti-theft device, which can improve accuracy of BLUETOOTH anti-lost notification, and avoid erroneous vibration notification in a non-lost case, where the method includes determining whether a step count value in first preset duration before a connection between an anti-theft device and a peer device is disconnected is greater than a preset value; if the step count value is greater than the preset value, determining whether a signal quality value sequence of a communication signal between the anti-theft device and the peer device shows a progressively decreasing trend in the first preset duration before the connected is disconnected; and giving an alarm if the signal quality value sequence shows a progressively decreasing trend in the first preset duration before the connected is disconnected.