Lung cancer is the first cause of death among malignant tumors, and the differentiation between early atypical lung cancer and benign lesions has always been a difficult task in imaging. CT-guided percutaneous lung aspiration biopsy can accurately display the condition of the lesion itself and the anatomical relationship with the surrounding tissue structures, and can precisely determine the needle entry site, angle and depth, which has a high correct diagnosis rate and safety factor. Pathological diagnosis plays a crucial role in the treatment of lung cancer today and is the only credible gold standard for lung cancer diagnosis. According to the literature, the diagnostic accuracy of this method is 74% to 99%. It indicates that this technique has a high accuracy rate for the diagnosis of lung occupying lesions, especially for cases that cannot be clearly diagnosed by fiberoptic bronchoscopy and sputum cytology, and has an important diagnostic and differential diagnostic value, and is an important auxiliary diagnostic tool for clinical diagnosis of lung cancer. In order to improve the accuracy of lung puncture biopsy and reduce complications, we believe that the following points should be noted: 1. 2.Check out, clotting time and platelet count before puncture, give sedative or cough medicine to those who are nervous or coughing before operation, actively communicate with patients to eliminate their fear and actively cooperate with the operator. 3. Choose the appropriate position to make the patient more comfortable, facilitate fixation and facilitate puncture, and shorten the operation time. 4.Train the patient to breathe, and ask the patient to breathe steadily and hold his breath during the localization scan; during the puncture, the patient should hold his breath with the same amplitude of steady breathing as much as possible to avoid damage to the pleura and small nodule localization deviation caused by breathing movement. 5. Select the lesion close to the chest wall or the nearest level, taking into account avoiding the ribs, scapula or other important organs. Qiu Minjian et al [4] found that the occurrence of complications was positively correlated with the depth of the lung tissue through which the puncture needle was inserted, with the incidence of complications exceeding 50% when the depth of the lung tissue through which the puncture needle was inserted exceeded 2 cm. 6, the size of the puncture needle to 18G is more appropriate. Needle too thick, heavy damage to lung tissue, prone to complications; needle too fine tissue specimens too little, affecting the pathological diagnosis. 7, avoid puncture to the necrotic area of the mass lesion, should be taken at the edge of the lesion, especially the area of enhanced tissue reinforcement is obvious, the lesion combined with pulmonary atelectasis, the two should be distinguished. 8, puncture specimens promptly fixed with 10% formaldehyde and promptly sent to the disease examination. The most common complications of using percutaneous lung puncture biopsy are pneumothorax and pulmonary hemorrhage, and the literature reports that the incidence of pneumothorax is 10% to 30% [5], but only 1.6% to 14.3% of patients require clinical closed chest drainage. In our group, there were five cases of pneumothorax with an incidence of 20.8%, all of which were small amounts of pneumothorax and did not require closed chest drainage. In general, the smaller the nodal lesion, the farther it is from the chest wall, the more difficult it is to locate it, and the thicker the puncture needle, the more likely it is to cause pneumothorax; pneumothorax almost never occurs when the needle is inserted from the large part of the lesion close to the chest wall. The operator should try to adopt the vertical approach when inexperienced, and the restrictive postoperative position with the puncture site facing downward helps to prevent pneumothorax. Pulmonary hemorrhage is overwhelmingly mild, manifested only by a post-puncture CT scan lung window showing a few faint patchy or cloudy shadows along the distribution of the needle tract or at the edge of the lesion, which can be observed. Two cases in this group showed symptoms of coughing up blood, one case was coughing up blood sputum after puncture, which was not treated and healed spontaneously after observation; the other case showed coughing up blood immediately after cutting because the lesion was close to the right lower pulmonary hilar, and the symptoms were relieved after immediate injection of hemostatic agent and healed spontaneously after 2h observation. Complications such as hemoptysis, subcutaneous emphysema, needle tumor implantation, mediastinal emphysema, air embolism, etc. are rare with percutaneous lung aspiration biopsy, and most literature also suggests that lung cancer dissemination or implantation metastasis will not occur. In conclusion, CT-guided percutaneous lung aspiration biopsy is a minimally invasive, safe and accurate examination method, which is easy to perform, inexpensive, with few complications, and acceptable to most patients, and is extremely helpful for the clinical diagnosis of intrapulmonary lesions, treatment planning and prognosis.