Objective To study facial function after large acoustic neruomas resections and identify factors which influence these outcomes.Methods A total of 127 cases acoustic neuromas were microsurgically removed via retrosigmoid approach using electromyo-graphy monitoring at neurosurgical department of Xiangya hospital from 2002.1-2008.4. by the senior surgeon (professor Yuan xianrui, MD & PHD). A retro-spectively reviewed was performed. Outpatient clinical follow-up every 3 months includes evaluation of facial nerve function. The facial nerve function was assessed using House-Brackmann facial nerve grading system.Results Of 125 cases of complete removal and 2 cases of deliberately partial removal, the facial nerve was anatomically preserved in 126 of 127 cases (99.2%) and preservation is supported by special electrophysiological monitoring. The non-parameter analysis and test for linear trend showed that tumor size (P<0.005) and early facial nerve function (P<0.0001) correlated with the facial nerve function at 1 year or more postoperatively. Patient age, symptom duration、cystic change, and preoperative hydrocephalus did not influence facial nerve function.Conclusions Resection of acoustic neuroma via retrosigmoid approach using electromyography monitoring is a safe and effective method. The long-term facial nerve function correlates with early facial nerve function (P<0.0001) and tumor size (P<0.005).