CT is the most accurate method for guiding fine needle biopsies in deep and/or small sized lung and mediastinic lesions. The authors have performed 2109 CT-guided lung biopsies (FNAB). The results are given in terms of sensitivity, specificity and rate of complications. In ever examination, Westcott or Chiba needles (22 or 21 gauge) were used. From 2109 lung examinations performed, 1413 (66.99%) were positive, 538 (25.5%) negative, 15 (0.7%) suspicious and 143 (6.78%) inadequate for diagnosis, 267 patients underwent surgical or clinical follow-up and, in all cases, the cytological diagnosis was confirmed. Other considerations were made on lesion topography, histological type, dimensions, complication rate, sensitivity, specificity and diagnostic accuracy. CT, of course, is the best method for guiding fine needle biopsy of the lung for its high spatial resolution and excellent anatomical definition, so that samples with smaller than 2 cm lesions, even in continuity with large vessels or other critical organs, are performed. Nevertheless, the result quality depends on the ability of the operator.