Percutaneous retrogasserian gangliolysis is suitable for treatment of trigeminal neuralgia because it is simple and effective. Further, it can avoid severe complications such as anesthesia dolorosa or dysesthesia that may develop after surgical procedure. However we have experienced an anesthesia dolorosa(pain in an area or region that is anesthetic) after percutaneous retrogasserian glycerol injection. This deafferentation pain is characterized by scratching, burning or itching sensation; and has shown to be of higher incidence in older and inemotionally unstable patients. Anesthesia dolorosa is relatively rare but difficult to treat. Consideration should be made for the complication which may develop during the procedure.