CT-guided histological sampling is nowadays used routinely in the differential diagnosis of focal lung diseases with no characteristic morphology. The aim of this study was to determine the value of the method. CT-guided core biopsy was performed in 25 patients with pulmonary nodules. 16 patients underwent bronchoscopy where cytological sampling was also carried out, while 5 patients underwent fluoroscopically guided biopsy. The histological diagnosis resulting from CT-guided biopsy specimens was compared with the findings from the other diagnostic procedures (bronchoscopy or fluoroscopically guided biopsy), with the results of surgery and/or chemotherapy and with the follow-up data. The result of CT-guided biopsy was true in 20/25 and falls in 5/25 cases. Of the 16/25 patients undergoing bronchoscopy, 13/16 gave negative results. In 11/16 cases, the result of the CT-guided biopsy was positive. The fluoroscopically guided biopsy was negative in 4/5 cases, and in 3/5 of these cases the diagnostic CT-guided biopsies proved positive. Our results demonstrate the better diagnostic value of CT-guided core biopsy relative to fluoroscopically guided biopsy or bronchoscopic sampling in those cases where the size and localization of the nodule make it inaccessible with the latter two methods.