Pulmonary scar carcinoma (PSC) is a specific type of peripheral lung cancer based on pulmonary scarring caused by lesions such as tuberculosis, pulmonary infarction and chronic inflammation of the lung, with heterogeneous proliferation and carcinogenesis of the fine broncho-alveolar epithelium in and around the scar tissue. The incidence reported in the literature is 4.1% to 7.8%. The following points should be noted in the diagnosis of this disease: (1) Chronic bronchitis of more than 10 years, pulmonary tuberculosis over 45 years of age, or recurrent inflammation in the same lung field in recent years should be alerted to PSC. (2) Patients with old tuberculosis presenting with cough or with sputum blood and retesting for antacid bacilli should be alerted to tuberculosis scar carcinoma. (3) Round lesions at the margins of the lung fields should be noted for the presence of the X-ray signs often seen in PSC, i.e. lobulated or burrily margins in the peripheral part of the upper lobe of the lung with pleural depression sign, tail sign or rabbit ear sign. When old tuberculosis foci appear as faint lamellar shadows in chest radiographs, attention should be paid to the series of chest contrast to be alert for PSC. (4) The diagnosis of this disease is confirmed mainly by pathological examination. The tumor is mostly located within 1 cm below the dirty pleura in the peripheral part of the lung, and the lesion is mostly <4 cm in diameter, accompanied by dirty pleural thickening, scar wrinkling or umbilical depression; microscopic examination reveals scar nodules of varying sizes composed of dense connective tissue, with abnormal elastic fiber hyperplasia, massive carbon end deposits, dense collagen fibers, occluded or mechanized blood vessels, and fine bronchial epithelial cells or alveolar cells can be seen in or around the scar nodules Abnormal proliferation or carcinogenesis may occur. PSC is mainly treated with a combination of surgery, chemotherapy and radiotherapy, but its malignancy is high and it is prone to lymphatic or hematogenous metastasis, and its prognosis is poor.