Abstract: Objective: To investigate the clinical application of microvascular decompression assisted by an neuroendoscope for treatment of trigeminal neuralgia.Methods: Seventeen cases of trigeminal neuralgia were treated by retromastoid key hole approach with microvascular decompression assisted by an neuroendoscope.The duty vessel and the arachnoid around the nerve were dissociated,then a fasciai patch was placed between the duty vessel and the trigeminus.Results: Thirteen patients were completely cured immediately after operation and 4 patients were relived of the pain 3 days after operation.Face dysesthesia occurred in 1 case and slight paralysis in 1 case.Both of them recovered 3 months after operation.No successive intracranial hemorrhage,postoperative infection or cerebrospinal fluid leakage were observed.No death ocurred.During the follow-up of 6 months to 4 years,1 patient recurred.Conclusions: neuroendoscope or microvascular decompression assisted by an neuroendoscope is one of most effective methods for treatment of trigeminal neuralgia.The advantages include a clear operation field(devoid of losing duty vascular or damaging the blood vessel,nerve and brain tissues),less postoperative complications and a high cure rate.