Vocal cord paralysis commonly results from the accidental severing of the recurrent laryngeal nerve or of one of its extralaryngeal branches during thyroidectomy.

Other causes include pressure from an aortic aneurysm or from an enlarged atrium (in patients with mitral stenosis), bronchial or esophageal carcinoma, hypertrophy of the thyroid gland, trauma (such as neck injuries) and intubation, and neuritis due to infections or metallic poisoning. Vocal cord paralysis can also result from hysteria and, rarely, lesions of the central nervous system.