“Orofacial diseases treated by Hegu(LI4)” is an important embodiment of the research on the links between meridians surface and surface.So to uncover the mechanism of Hegu(LI4) being effected for orofacial may be an important breakthrough point of “Orofacial diseases treated by Hegu(LI4)” from the angle of neurobiology.Pain threshold and EMG activity of Orofacial，the secretion of saliva and the central brain functional network response were observed when acupuncturing in Hegu(LI4)，with HouXi(SI3) and Waiguan(SJ5) as control acupoints in this article，so as to explore the neurobiological basis of specific relation between Hegu(LI4) and orofacial from the different levels.