Abstract: Objective: To analyze the clinical solitary pulmonary nodules（SPN） less than 30mm in diameter. Methods: Clinical data of 212 patients with SPN admitted to our hospital from January 2007 to March 2008 were reviewed.Clinical differences in benign and malignant SPN were compared. Results: The male and female ratio was 1.5∶1.0.No specificity was observed in clinical manifestations of SPN and over 50% of clinical manifestations of SPN were discovered at routine examinations.Computed tomography was used to detect the lesions before operation.All patients underwent surgical resection of SPN and malignant SPN were found in 149 cases（70.3%）. Conclusion: Malignant SPN were much more common than benign SPN.SPN should be detected at their early stage and surgically removed.