He-Ne laser therapy has been trially applied to 55 cases of various kinds of deseases in oral and maxillo-facial surgery using SOFT LASER 632 of Mainfar Ltd., and their clinical applicability to this field has been survayed evaluating the therapeutic effects. As the results, the laser was proved to have anti-inflammatory effect, activating effect on wound healing, analgesic effect and so on, as well as popularly known. In addition to these, depigmentation effect on vasculargenous nevus in oral mucosa has been newly found.