Occupational lesions in the lower lobe of the left lung may be related to lesion scarring, inflammatory shadows, lung tumors and other factors, and different therapies are adopted for different causes. 1. Lesion scar: If the occupying lesion in the lower lobe of the left lung does not change in shape, density and size after a long time of imaging, it may be a post-inflammatory scar, which has clear boundaries and a round or oval shape, but the specific nature needs to be determined by pathologic examination. At this time, no special symptoms generally do not need treatment. 2. Inflammation: If it is a dense shadow with uniform density, it may be pneumonia, which can be comprehensively determined by blood test. Usually, after anti-infection treatment, the shadow of inflammatory lesions can be gradually reduced or dissipated. Common therapeutic drugs include antibiotics, glucocorticoids, ibuprofen, acetaminophen, which are mainly used for anti-inflammatory and anti-infectious treatment and antipyretic treatment. 3. Lung tumor: if the imaging edge of the occupying lesion is smooth, it is mostly benign tumor; if the edge is fuzzy or there is infiltration burr phenomenon and the range is gradually increasing, it is suggestive of malignant tumor. Common drugs include penicillin, posterior pituitary hormone, gemcitabine, cisplatin, and gefitinib. Surgical resection is the preferred treatment for high-risk symptomatic lung tumors. If occupational lesions in the lower lobe of the left lung are found, timely medical treatment should be sought under the guidance of the doctor, and unauthorized medication should not be used to avoid delaying the condition. Pay attention to rest on weekdays, quit smoking and drinking, and keep a regular routine.