The causes of hoarseness are generally several: 1, hoarseness due to acute congestion and edema of the vocal cords caused by inflammatory infections. The reason for this is that it is necessary to take oral anti-inflammatory medication, along with nebulized inhalation forbidden sound, for about 1 week. 2, vocal cord neoplasm, such as vocal cord nodule polyp, vocal cord malignant tumor, need to go to the hospital to check the laryngoscope, you can clearly diagnose, if necessary, need to take pathology. First diagnosis and then treatment, if it is vocal cord nodules or vocal cord polyps, need surgery; if it is malignant tumor, need to first systemic examination, whether it is accompanied by local spread, and then surgery, surgery according to the scope of the tumor and the spread of the scope. 3, neurological lesions: such as viral infection, or surgery, trauma, tumor compression and other factors caused by laryngeal nerve damage or vagus nerve injury. 4. Dislocation of the cricoarytenoid joint, etc.