There are three common causes of hoarseness, one is congenital developmental abnormalities, the second is due to inflammation, and the third is localized tissue hyperplasia of the vocal folds. 1. Congenital developmental anomalies: such as congenital laryngeal webbing, etc., most of the patients have hoarseness since childhood, and is not accompanied by obvious discomfort. 2. Inflammation: Inflammation causes the vocal folds to become congested and swollen, leading to poor closure of the vocal folds, resulting in hoarseness, often accompanied by redness, swelling and pain in the throat. 3. Localized tissue hyperplasia of the vocal cords: benign ones include vocal cord nodules and vocal cord polyps, while malignant ones include laryngeal cancer. In the case of hoarseness caused by vocal cord polyps and vocal cord nodules, the patient has a history of excessive use of voice, which can be recovered after restricting the intensity of voice use for a period of time. The exact cause of hoarseness should be clearly diagnosed after examination by a specialist.