Coughing up green sputum is more common in clinical practice in respiratory diseases caused by both infectious and non-infectious factors. Infectious factors can be seen in inflammation of the respiratory tract caused by mycoplasma, chlamydia, rickettsia, and fungi. Non-infectious factors can be seen in bronchial asthma, cough variant asthma, chronic bronchitis, and bronchiectasis. In addition, the presence of these factors can be clarified by X-rays and CT of both lungs, as well as by taking sputum for pathogen culture and performing pulmonary function tests, and the disease should be treated symptomatically and etiologically in a timely manner.