Abstract To evaluate the combination of transbronchial biopsy (TBB) using endobronchial ultrasonography with a guide sheath (EBUS-GS) and positron emission tomography with fluorodeoxyglucose (FDG-PET) for the diagnosis of small peripheral pulmonary lesions (PPLs) ≤30 mm in mean diameter. A total of 74 PPLs (69.2%) were diagnosed by TBB using EBUS-GS with X-ray fluoroscopy. Diagnostic yield by FDG-PET was 78.5% for the 107 PPLs examined. Diagnostic yield with the combination of TBB using EBUS-GS and FDG-PET (90.7%) was significantly higher compared with that for each procedure alone. A significant increment in diagnostic yield with this combination was seen for PPLs >20 mm and ≤30 mm and for malignant lesions. Combination of TBB using EBUS-GS and FDG-PET is useful for the diagnosis of small PPLs.