Spasmodic dysphonia (SD), a kind of dysphonia due to focal muscle spasm of the larynx leading to laryngeal movement disorder, is not rare clinically and is divided into inward and outward types. The former is common, mainly manifesting as changes in voice quality, phonation and fluency of speech, tension dysphonia, speech tremors, instantaneous ups and downs in frequency and loudness, voice squeezing and interruption, speech prolongation and loss of normal rhythm when reading aloud; the latter is rare. To diagnose spasmodic dysphonia, first of all, we should ask the neurology department for consultation to exclude the articulatory tremors caused by central diseases, and also ask the psychology department for consultation to exclude the functional dysphonia caused by psychological factors. After the above diseases are excluded, dynamic laryngoscopy and laryngeal electromyography should be performed by a voice specialist to determine whether the laryngeal muscles are hyperfunctional. The diagnosis can then be determined. So far, the treatments for spasmodic dysphonia are broadly divided into: 1) medication, 2) surgery, and 3) botulinum toxin injection. The most effective method is Botox injection treatment. 8-24 hours after the injection, the patient’s symptoms can be significantly relieved and the speech can be fluent, but there is no permanent effect, the effect lasts about 3 to 6 months, the symptoms will recur, it is necessary to repeatedly inject several times, but according to different patients, the dose of injection can be appropriately reduced. The injections need to be performed under electromyography guidance, and Botox is precisely injected into the corresponding intralaryngeal muscles, and the inward type is more effective than the outward type. However, Botox injections are only symptomatic treatment.