Sudden hoarseness of the voice generally refers to hoarseness, which may be caused by inflammation, trauma, tumor, neuropathy and other factors. 1. Inflammation: when the upper respiratory tract is infected by pathogenic microorganisms such as bacteria and viruses, it may lead to congestion and edema of the mucosal tissues in the throat, and the patient will experience hoarseness, and the common diseases include colds, laryngeal tuberculosis, laryngeal diphtheria and so on. 2. Trauma: when the vocal organs are traumatized, it will lead to abnormal vocalization and symptoms of hoarseness, and the common traumas are explosion injury, smoke injury, burn injury and so on. 3. Tumor: Tumor invades the vocal organs and presses the nerves innervating the voice, which will lead to hoarseness, such as lung cancer, thyroid cancer, laryngeal cancer and so on. 4. Neurological diseases: When the nerves controlling the vocal organs are diseased, the voice will be affected and hoarseness will appear, and common diseases include laryngeal reentrant neuritis, laryngeal reentrant nerve injury and so on. Sudden hoarseness may also be related to hysteria, laryngeal webbing, cricoarytenoid arthritis, etc. It is recommended that the patient consult a doctor in time to find out the cause of the disease and carry out the relevant treatment.