Objectives: We investigated the sensitivity of preoperative clinic and radiologic evaluations in predicting difficulty dur-ing intubation. Patients and Methods: The study included 165 patients in whom difficult intubation was not estimated during general anesthesia. Preoperative measurements included the interincisural gap, thyromental and sternomental distances, mastoid-sternoclavicular joint distance, neck circumference at the cricoid level, the length of ramus and corpus mandible, and the mandibular angle. Intraoral structures were evaluated according to the Mallampati classification. On lateral cervical graphies of the neck, the atlanto-occipital distance, mandibular angle, mandibulo-hyoid distance, cervico-hyoid distance, and the mento-hyoid distance were measured. The appearance of the larynx was evaluated according to the Cormack and Lehane (C-L) classification. The relationship between measurements and difficulty of intubation was analyzed and the findings were compared with those of a control group of 50 outpatients. Results: Difficult intubation was determined in three patients (%1.8) during laryngoscopy. One of these patients was classified as C-L IV and the other two as C-L III. There was no cor-relation between the Wilson classification and other clinical measurements. The Mallampati classification showed a positive correlation with age (p=0.000), and a negative correlation with the sternomental distance (p=0.023). We found a positive correlation between the C-L classification and body weight (p=0.048), and neck circumference (p=0.000). The cervico-hyoid distance and the C-L classification were positively correlated according to radiological measurements (p=0.039). Conclusion: Lateral cervical graphies on neutral and hyperextension position may give additional information on possible difficult intubation preoperatively.