Objective To investigate the clinical effects of botulinum toxin A ( BTX-A) local injection treatment for hemifacial spasm .Methods Seventeen sites were used to inject BTX-A in 46 patients with hemifacial spasm . Before and after treatment , the grades of facial spasm were evaluated .Clinical efficacy was evaluated based on hemifacial spasm rating 4 weeks after treatment .The recurrence of symptoms in patients given repeated BTX-A injection.Results After BTX-A injection, 15 cases of completely relieved , obviously relieved in 29 cases, partial remission in 2 cases;the efficiency was 95.6%.The onset time was (2.6 ±1.1) d;sustained efficacy was (19.1 ± 2.3)weeks.Injection times was 1 in 5 cases, 2 in 23 cases, 3 in 11 cases and 4 or more in 7 cases.The onset time of repeated injection was(2.61 ±1.03) d, the duration was(19.24 ±2.12) weeks and the efficiency was 100%, They had no significant differences between initial and repeated injection .Six cases occurred local facial mild paralysis, and complete recovery after 2-4 weeks.Conclusion BTX-A local injection for hemifacial spasm is a safe and effective treatment , has no significant adverse reaction;and the effect of repeated injection is not decreased .