We conducted a prognostic study of 78cases with hemifacial spasm by questionaire from January to June, 1980. On the avarage 11.5 years had passed since consultation with a physician. There were 44 respondents, the response rate being 56.4 percent. Excluding 2 deceased, the results obtained from 42 cases were compared mainly with the reports of Ehni and Wakasugi. There were 29 female cases(69.0%) and 13 male cases (31.0%). As to the age at onset, the disease started from the age of 20 on but developed most frequently in their 20s-50s. Aggravation of symptoms due to psychological stress was seen in many of the cases. Three cases (7.0%) showed a family history of facial spasm. According to the clinical course after medical treatment, 7cases became worsen (15.9%), 10 remained unchanged (22.7%), 20 improved (45.5%), 5 remitted (11.4%) and 2 died (4.5%), which was nearly in agreement with the results of Ehni. As to the treatment, pharmacotherapy led to improvement in symptoms in about half of the cases but the duration of effectiveness was not satisfactory. As for fifteen cases which had been under facial nerve block, all but one case showed recurrence of the symptoms within three years. Psychological factors were concerned with the clinical course of this disease. In the treatment, therefore, it appeared necessary to give enough consideration to the psychosomatic aspect.