Abstract: The nature of solitary pulmonary nodules(SPN) are commonly identified by chest radiographs and computerized tomography(CT) which can't find out accurately the malignancy in general. Biopsies are often performed to evaluate the nodules further.However it can induce complication or death. As a safe and non-invasive method, characterized by high sensitivity, high specificity and high accuracy in differentiations between benign and malignant SPN, PET can decrease greatly the number of unnecessary diagnostic thoracotomy and related operation cost. So it would be used widely in the future.