ObjectivesTo explore the role of nodule-pleural relationship, including nodule with pleural tail sign (PTS), nodule with pleural contact and nodule with pleural unrelated in CT-guided percutaneous transthoracic needle biopsy (PTNB)-induced pneumothorax, and whether employing different puncture routes has an impact on the incidence of pneumothorax in PTNB of nodules with PTS.MethodsBetween April 1, 2019, to June 30, 2021, 775 consecutive PTNB procedures of pulmonary nodules in the Peking University Cancer Hospital were retrospectively reviewed. The univariate and multivariate regression analysis were used to identify the risk factors for pneumothorax in PTNB.ResultsThe nodule with pleural contact group has a lower incidence of pneumothorax than the nodule with PTS group (p = 0.001) and the nodule with pleural unrelated group (p = 0.002). It was observed that a higher incidence of pneumothorax caused by crossing PTS compared with no crossing PTS (p < 0.001). Independent risk factors for pneumothorax included crossing PTS (p < 0.001), perifocal emphysema (p < 0.001), biopsy side up (p < 0.001), longer puncture time (p < 0.001), deeper needle insertion depth (intrapulmonary) (p < 0.001) and nodules in the middle or lower lobe (p = 0.007).ConclusionPatients with crossing PTS, a nodule in the middle or lower lobe, longer puncture time, biopsy side up, deeper needle insertion depth (intrapulmonary), and perifocal emphysema were more likely to experience pneumothorax in PTNB. When performing the biopsy on a nodule with PTS, selecting a route that avoids crossing through the PTS may be advisable to reduce the risk of pneumothorax.