A method for setting a device identifier comprises: obtaining a first APP (Application) list of a target device; performing matching between the first APP list and a second APP list to determine a number of identical APPs in both the first APP list and the second APP list; determining whether the determined number of identical APPs reaches a pre-set threshold; and when the determined number of identical APPs reaches the pre-set threshold, setting a device identifier corresponding to the second APP list as the target device's device identifier.