Facial complex regional pain syndrome (CRPS) is a CRPS that occurs around the periorbital and/or orofacial region, showing regional chronic pain accompanied by motor and autonomic nervous dysfunction. At present, the pathogenesis of CRPS is not clear, which may include inflammatory reaction, sympathetic nerve, spinal cord, supraspinal and other mechanisms. It is related to the hemisensory disturbances of CRPS, and closely associated with facial allodynia and migraine with trigeminal nerve. This article reviews the possible mechanisms of facial CRPS and connects the limb pain with facial pain, in order to provide some reference for the study of the pathogenesis of CRPS.