The invention belongs to the technical field of mobile terminals, and provides a face-recognition light supplementing method, a face-recognition light-supplementing device, a mobile terminal and a computer-readable storage medium. The method comprises the following steps: acquiring the current ambient light intensity when a face recognition function is started; if the current ambient light intensity is less than a preset threshold value, selecting a target light supplementing mode from a plurality of different light supplementing modes according to the current ambient light intensity; and performing light supplementing on the face according to the target light supplementing mode. The face-recognition light-supplementing method, the face-recognition light-supplementing device and the mobileterminal can solve the problem that the success rate of face recognition is low when the ambient light is insufficient in the prior art.