Introduction: The diagnosis of peripheral pulmonary lesions (PPL) poses a significant challenge, prompting the widespread utilization of various modalities to ensure the precision in diagnosis. This study aims to assess the diagnostic accuracy of computed tomography guided percutaneous transthoracic needle biopsy (CT-PTNB) in the context of pulmonary malignancy. Methods and materials: This multicenter retrospective observational study, included 1317 cases of CT-PTNB performed on adult patients with PPLs during January 2018 to December 2022, in Mashhad, Iran. The pathology results of CT-PTNB from 94 cases were compared to the definitive pathology results obtained through methods such as surgery to assess the sensitivity, specificity, and overall accuracy of CT-PTNB in diagnosing of pulmonary malignancy. Results: CT-PTNB exhibits an accuracy of 82.98%, with sensitivity and specificity rates of 75.41% and 91.43%, respectively. This study underscores the issue of false-negative results in CT-PTNB and underscores the importance of integrating clinical, radiological and additional diagnostic modality to guide diagnostic decisions. Conclusion: In this large scale multicenter study, the accuracy of CT-PTNB for diagnosis of pulmonary malignancy is acceptable but fairly low compared to previous studies.