Abstract: Objective To investigate the efficacy of microvascular decompression(MVD) on patients with primary hemifacial spasm(HFS)and sum up experiences to enhance the curative effects and decrease complications. Methods The data of 57 patients with HFS during June,2010 to June,2015 who had underwent MVD were retrospectively analyzed for the efficacy and complications. Results Fifty-six patients had specific one or more offending vessels,accounting for 98.2 percent,which were respectively anterior inferior cerebellar artery,posterior inferior cerebellar artery as well as vertebral artery.There was no specific offending vessel in one case.Significant vascular pressure trace was seen in facial nerve root of 12 patients in operation.Hemifacial spasm immediately disappeared in 8 patients and hemifacial spasm was obviously relieved in 4 patients after operation.Among 57 patients,symptoms of HFS disappeared immediately after operation in 51 patients and significantly relieved in 6 patients,the symptoms of whom gradually disappeared in 6 months later.Slight facial paralysis appeared in 6 patients after operation and gradually disappeared in 5 patients 6 months later.There was 1 patient with mild facial paralysis followed up for 2 years.Hearing impairment appeared in 5 cases after operation and there was no obvious improvement in 6 months to 2 years.Permanent hearing loss appeared in 1 patient after operation.Tinnitus appeared in 2 patients after operation and disappeared 3 months later.Dizziness and ataxia appeared in 2 patients after operation and disappeared in 1 month.There was neither report of cerebrospinal fluid leakage and intracranial infection,no report of disability and death.No recurrence was noted during the follow-up period of 1 to 4 years(mean 2.5 years). Conclusion MVD is a safe and effective treatment for HFS.Effect of MVD for elderly patients with HFS was satisfying,thus age was not a contraindication of MVD.MVD,with high cure rate and low complication rate,should be the first choice for the treatment of HFS.Solid theoretical foundation and skilled micromanipulation technique are essential to improve the curative effect and reduce complications.