This prospective study, based on 13 patients with single pulmonary nodules of width between 10 and 30 mm, was performed to verify the utility of intrathoracoscopic ultrasound to localize the single pulmonary nodule. In all 13 cases the ultrasound examination was able to localize the position of nodules, but the homogeneous hypoechoic pattern of nodules observed in ten of 13 cases did not prove whether the lesion was benign or malign. In conclusion, we can confirm that intrathoracoscopic ultrasound examination is a safe, risk-free and less expensive method of localizing the single pulmonary nodules.