Yellow sputum in the throat is clinically seen in the following diseases: 1. Acute pharyngitis, such patients will have acute diffuse congestion in the throat, hyperplasia and congestion of lymphoid follicles in the posterior pharyngeal wall and the root of the tongue, with pus on the local surface, and purulent secretions will be spit out in the form of sputum. Clinically, for this condition, blood sampling for routine blood tests is recommended. In case of serious infection, treatment such as intravenous infusion can be considered. 2. Some patients have chronic sinusitis, and long-term nasal discharge flows backwards into the throat and becomes phlegm. In this case, it is possible that the throat itself is not a big problem, but mainly the patient has the possibility of sinusitis. The main treatment for sinusitis in this case is symptomatic treatment with clinical application of antibiotics, mucus promoters, and nasal rinses. When sinusitis improves, phlegm inside the throat is basically absent; 3. Some patients, for example, have chronic bronchitis, infection in the lungs, long-term cough and cough, which will also manifest as phlegm in the throat. Therefore, if a patient has phlegm in the throat, it is recommended that the patient go to the ENT department for a comprehensive and thorough examination of the sinuses, nasopharynx, pharynx, and trachea.