Laryngeal muscle weakness is defined as a weak voice, vocal leakage, singing out of tune, inability to sustain speech, and hoarseness if one speaks more than one word; examination reveals shortening of the vocal time, narrowing of the vocal range, bilateral retraction of the vocal folds, and incomplete closure. It is mostly seen in people with old age, kidney failure and overworked voice, mostly due to lack of vital energy and strain on the laryngeal muscle, unlike myasthenia gravis or neuropathetic diseases. Vocal fold closure insufficiency is a disease of vocal folds that is caused by insufficient movement of the laryngeal muscles during vocalization, and is also a disease of laryngeal muscle weakness and vocal fatigue. Differential diagnosis of laryngeal muscle weakness is noted for the following diseases: 1. Severe myasthenia gravis: Although only a few patients show pharyngeal symptoms, most have laryngeal muscle involvement. For patients who visit the clinic because of weak voice and hoarseness and difficulty in pronunciation, myasthenia gravis should be considered as a necessary differential diagnosis. 2, vocal fold dyskinesia: vocal fold dyskinesia is a type of disease caused by abnormal vocal fold motor function with dysphonia as the main clinical manifestation. It can be divided into neurological, muscular, arthritic and functional.