[Background] Due to the low diagnostic yield of bronchoscopy for small peripheral pulmonary lesions (PPLs), various procedures have been introduced to improve its accuracy. Recent studies demonstrated the integration of cone-beam CT (CBCT) into the process, although its effectiveness has not been established. [Aims] To determine the additional value of CBCT in ultra-thin bronchoscopy. [Methods] A total of 91 patients who underwent transbronchial biopsy using CBCT for PPLs ?2 cm between June 2019 and August 2021 were enrolled. The following factors were included in our retrospective analysis to determine whether they contribute to the diagnosis: age, lesion size, lesion morphology, lesion location, involvement of bronchus, involvement of pulmonary artery, endobronchial ultrasound (EBUS) findings (within, adjacent to, or invisible), CBCT findings (relationship between forceps and lesions), and whether the forceps position was adjusted after CBCT. Virtual bronchoscopic navigation and EBUS were used in all cases. [Results] Patients had a median age of 71 years (range: 46-86 years), with the lesion size ranging from 6 to 20 mm (median: 13.5 mm). The diagnostic yield was 49.5%. On multivariate analysis, factors that contributed significantly to the diagnosis were morphology (solid: 60.3%, part solid + pure ground glass nodule: 30.3%, p<0.05, odds ratio (OR)= 3.7, 95% CI: 1.4-9.7), location (distal: 58.1%, middle + proximal: 31.0%, p<0.05, OR=3.1, 95% CI: 1.1-8.6), and CBCT findings (center + inside: 60.5%, edge + outside + fault: 39.6%, p<0.05, OR= 2.8, 95% CI: 1.1-7.2). [Conclusion] CBCT may be used effectively with ultra-thin bronchoscopy for the diagnosis of small PPLs.