Cough with yellow sputum is mainly seen in acute bronchitis, pneumonia, bronchiectasis, chronic obstructive pulmonary disease and other diseases. 1. Acute bronchitis: viral infection, bacterial infection and other infections can cause bronchitis, patients will have cough, cough yellow sputum, fever and other symptoms. 2. Pneumonia: Pneumonia patients may have cough, cough yellow sputum, myalgia, fatigue, headache, sore throat and other symptoms. 3. Bronchiectasis with acute infection: repeated respiratory tract infections and inflammation can cause bronchiectasis. When bronchiectasis with acute infection, patients may have cough, sputum, hemoptysis and other symptoms. 4. Acute exacerbation of chronic obstructive pulmonary disease (COPD): patients with COPD combined with bacterial infections will experience acute exacerbation, coughing, coughing up pus and sputum, wheezing and other symptoms. The symptoms of cough with yellow sputum, it is recommended to go to the hospital in time.