When there is blood in the sputum after smoking, it may be caused by the following diseases: 1. Bronchiectasis, which can appear as repeated coughing, coughing up pus sputum, sputum with blood, or coughing up a lot of blood, can be clearly diagnosed after perfecting lung CT, and comprehensive treatment such as anti-infection, expectoration, and wheezing should be given according to the condition after confirming the diagnosis of bronchiectasis. 2. Tuberculosis can appear with blood in the sputum, and the patient will also have The patient will have symptoms of tuberculosis poisoning such as low fever, weakness, night sweats, wasting, etc. Tuberculosis foci will appear in the lung CT, and the detection of antacid bacilli in the sputum can confirm the diagnosis of active tuberculosis, and anti-tuberculosis treatment should be carried out after the diagnosis. 3. Patients who have smoked for a long time and have blood in the sputum should be highly alert to pulmonary malignant tumors, and patients with pulmonary malignant tumors can have masses in the lung CT, and the diagnosis can be made clearly after bronchoscopy or puncture biopsy. After diagnosis, surgery, radiotherapy, chemotherapy and other comprehensive treatments can be given according to the condition.