The possible clinical causes of sore throat and yellow sputum in the morning are acute pharyngolaryngitis, tonsillar suppuration, and recurrent nasopharyngitis. 1. Acute pharyngolaryngitis: this condition refers to acute inflammation of submucosal tissues, which mostly involves lymph node tissues in the throat and is associated with infection of the mucous membranes in the throat. Typical manifestations of this disease include coughing up yellow pus sputum and sore throat. 2. Tonsillar suppuration: this condition refers to acute purulent infection of palatine tonsils caused by bacteria or viruses and other pathogens, and its common causative organisms include streptococcus, etc. Typical features include high fever, severe sore throat, coughing up yellow pus sputum and so on. 3. Repeated episodes of nasopharyngitis: This condition refers to repeated episodes of inflammation of the mucous membrane of the nasopharynx, submucosa and lymphatic tissue, which is related to environmental pollution, bacterial invasion and other factors, the clinical manifestations of nasal congestion, runny nose, frequent sputum coughing with yellow sputum and so on. There are other possibilities for a sore throat with yellow sputum in the morning, so it is recommended to consult a doctor in time to complete the relevant examinations and standardize the treatment.