Children with phlegm in the throat hoarse voice may be caused by upper respiratory tract infection, bronchitis, chronic pharyngitis and other diseases. 1. Upper respiratory tract infection: Upper respiratory tract infection is a general term for acute inflammation of the nasal cavity, pharynx or larynx, the cause of which is related to the pathogen infection, rain, cold, overwork are all triggers of upper respiratory tract infection. Patients will have cough, cough sputum, runny nose and hoarse voice and other symptoms. 2. Bronchitis: Bronchitis is caused by microbial infections, physical or chemical stimuli, the patient’s typical symptoms are coughing, coughing up sputum, some patients will also have hoarse voice symptoms, preferably in the elderly and young children. 3. Chronic pharyngitis: chronic pharyngitis is a chronic inflammation of the mucous membrane of the pharynx, submucous membrane and lymphatic tissue, patients will have a foreign body sensation, burning sensation, dryness, and itching and other symptoms, if the child suffers from chronic pharyngitis, there will be a throat with phlegm hoarseness symptoms. There are many causes of hoarseness in children’s throats, so it is recommended that family members take their children to the doctor for a checkup.