The possibility of malignant transformation of old tuberculosis is low, but there is a possibility that it may turn into scar cancer. There may still be dormant tuberculosis bacilli in old tuberculosis, which may lead to recurrence of tuberculosis. Tuberculosis may leave tuberculous scars in the lungs after treatment. If the scar tissue is exposed to external stimulation for a long time, cell mutation may occur, which may lead to scar cancer, but the possibility of occurrence is relatively small. If the tuberculosis bacillus in the old tuberculosis lesion recurs, the patient should consult a doctor in time for anti-tuberculosis bacillus treatment, such as isoniazid, rifampicin and other drugs. Patients with old TB should pay attention to regular checkups, strengthen nutrition, and pay attention to rest in order to prevent the recurrence of tuberculosis bacilli or the complication of lung diseases.