Smoking with black sputum is mainly seen in the following cases: 1. When the patient smokes for a long time, nicotine and tar in the cigarette are deposited in the mucous membrane epithelium of the respiratory tract after being inhaled in large quantities by the patient’s respiratory tract. When the patient coughs, the above substances are coughed out in the form of black substances, which are part of the black sputum. 2. When the patient smokes for a long time, the nicotine and tar and other harmful substances in the cigarette damage the mucous membrane in the airways and lungs, leading to the inflammatory reaction of the respiratory tract. The inflammatory reaction can produce filthy substances, which are also part of the black phlegm. 3, patients who smoke for a long time have chronic pharyngitis, and patients with chronic pharyngitis often cough up filthy substances from the throat, which are also part of the black phlegm. In conclusion, it is recommended that patients should immediately stop smoking when black sputum appears, go to the ENT department, respiratory medicine, and give relevant symptomatic treatment and treatment to avoid aggravation of the lesion and induce the appearance of lung cancer and other related malignant tumor-like diseases.