The symptoms of laryngeal cancer are mainly hoarseness, dyspnea, cough, dysphagia and cervical lymph node metastasis, sometimes foreign body sensation in the throat, bad breath and a small amount of coughing up blood may occur. The symptoms of laryngeal cancer are related to the location of the tumor. In early stage, even the tumor has developed to a considerable extent, it often has mild and non-specific symptoms, such as pharyngeal itching, foreign body sensation, swallowing discomfort, etc., which do not attract special attention of patients. If the tumor invades the arytenoid cartilage, paravocal fold or vocal cords, it may cause hoarseness. In late stage, patients will have difficulty in breathing, swallowing, coughing, blood in sputum, hemoptysis, etc. 2.Vocal hilar cancer, early symptoms are voice change, such as easy to pronounce fatigue and weakness, which can be easily considered as pharyngolaryngitis. Therefore, those who are over 40 years old and have hoarseness for more than 2 weeks and do not improve by vocal rest and general treatment should have careful laryngoscopy. Thereafter, hoarseness gradually worsens and vocal coarseness and hoarseness, or even loss of voice, may occur. Dyspnea is another common symptom of vocal tract cancer. Vocal fissure is the narrowest part of respiratory tract. When vocal fissure develops to a certain extent, it will affect the abduction of vocal folds, which will restrict and fix the movement of vocal folds, and together with the blockage of tumor tissues, laryngeal obstruction symptoms may appear. When the tumor tissue is necrotic, bleeding and infected, severe laryngeal obstruction can occur and requires emergency treatment. Vocal fold cancer is generally highly differentiated and develops slowly. Since there are fewer lymphatic vessels in the vocal fold, it is not easy for cervical lymph node metastasis to occur. Subglottic carcinoma, which is located below the plane of vocal cord and above the lower edge of cricoid cartilage, is easily misdiagnosed because of its hidden location and inconspicuous early symptoms, and therefore not easily detected by conventional laryngoscopy. 4.Transglottic carcinoma, a manifestation of laryngeal cancer, originates from one side of the laryngeal chambers, the tumor location is deep and hidden, so it is not easy to detect the tumor by laryngoscopy, its course is long and the tumor develops slowly, from the first hoarseness to the definite diagnosis, it takes more than half a year. Therefore, it is important to pay attention to any persistent discomfort in the larynx of middle-aged patients and above.