Percutaneous lung biopsy is an important part of pulmonary non-vascular interventional technique, and the nature of some lesions is difficult to be determined by imaging. The cytological and histological data obtained by biopsy can make qualitative diagnosis and differential diagnosis, which plays an important role in the selection and formulation of treatment plan, follow-up after treatment and prognosis prediction. Examination method: First, routine CT scan of the lung was performed, then the distance and angle from the puncture point to the scheduled puncture target were measured on the CT image, and the puncture point was routinely disinfected, covered with towel and locally anesthetized. Measure the puncture depth, let the patient hold his breath and puncture at a predetermined angle. Pay attention to keep the puncture needle in the same scanning plane of the puncture point, and try to use the direction parallel or vertical to the ground. After the puncture is in place, a local CT scan is performed to determine whether the needle tip is in the lesion. If it is necessary to adjust the direction, the puncture needle should be retreated to the chest wall for adjustment, or pulled out for re-puncture. When adjusting the puncture needle or pulling out the needle, ask the patient to hold his breath. When the needle is in the body, let the patient breathe calmly and try to avoid coughing. Exit the puncture needle after puncture, fix the puncture specimen and send it for pathological examination. In recent years, lung biopsy has been widely used in the diagnosis and differential diagnosis of clinical diseases. There are many non-vascular guided methods to achieve the purpose of biopsy or treatment. In medical imaging, CT and fluoroscopy, which technique to use depends on the location, size and nature of the lesion, the proficiency and habit of doctors and the proficiency of patients. CT-guided percutaneous lung biopsy is simple and has few complications. The biggest advantage of CT-guided puncture is that the density resolution of CT images is high, which can clearly show the size, cystic solidity, necrosis and its relationship with surrounding tissues and organs, without interference from gas, fat and bones, and the images do not overlap. Thin-layer scanning can be performed, and the position of the needle tip can be accurately positioned and judged. Therefore, the safety is good, the success rate of biopsy is high, reaching 90%, and the treatment effect is good. However, CT-guided puncture also has shortcomings: because it is not timely imaging, breathing movement will cause accurate positioning errors, so patients must be trained to master breathing phase. When the puncture needle needs to form a certain angle with the cross section, the puncture technology is difficult, and the angle of the frame can be adjusted.