Hemifacial spasm is an involuntary, irregular, clonic or tonic contraction of the muscles innervated by one side of the facial nerve. With the progress of the disease, the aggravation of hemifacial spasm symptoms may affect the daily life of patients, which in turn has a negative impact on the patient's mood. It is necessary to treat hemifacial spasm. As a safe and effective treatment, botulinum toxin injection can improve the symptoms of hemifacial spasm within 3-6 months. This article summarizes the diagnosis of hemifacial spasm and its impact on life, the treatment methods and principles of botulinum toxin on hemifacial spasm, and discusses the progress of botulinum toxin efficacy evaluation in hemifacial spasm, so as to provide reference for the efficacy evaluation of botulinum toxin in the treatment of hemifacial spasm.