We reviewed the records of 50 patients seen in the past 5 years between 1985 to 1990 who had an initial diagnosis of idiopathic sudden sensorineural hearing loss and had been treated with a course of stellate ganglion biock. We also studied the factors related to recovery. 1) The overall results, we obtained, were 17 patients(34%) of complete recovery, 6 patients(12%) of partial recovery, 7 patients(14%) of slight recovery and 20 patients(40%) of no improvement. 2) The factors related to recovery were severity of initial hearing loss, initial audiogram pattern, age, vertigo and duration from onset to initial treatment, but, not related to elevated erythrocyte sedimentation rate. 3) Most of recovery group responded within 20 times of stellate ganglion block.