Pulmonary nodules with clear margins are mostly benign, but a small percentage of pulmonary nodules with clear margins may be malignant. If a patient has a small diameter nodule with smooth margins in the lung, it is considered a benign nodule and is clinically reviewed on a regular basis. If the patient’s nodules are larger in diameter or have unsmooth margins, they are considered potentially malignant nodules and require further improvement of lung enhancement CT, puncture biopsy of the nodules, bronchoscopy and other related tests to clarify the diagnosis. If the diagnosis of malignant nodules is confirmed, surgery, radiotherapy, chemotherapy, targeted cell therapy, gene therapy, immunotherapy, etc. can be considered according to the condition.