Purpose : To determine the value of thin-section CT in the diagnosis of nasal bone fractures. Materials and methods : We evaluated the thin-section CT scans of 40 patients with nasal bone fracture. CT scans were obtained with both axial and coronal planes, 1.5mm collimation with 2mm interval, and 9.6cm field-of-view. The axial scan plane was kept parallel to the orbito meatal line from the nasion to the lower limit of the nose and the coronal plane was kept perpendicular to the axial plane. The data were reconstructed with bone algorithm. Nasal bone fracture was classified into 1 of 3 types on thin section CT: (I) simple fracture; (II) simple fracture with displacement; (III) comminuted fracture. Associated facial bone injuries were also evaluated. Simple radio graphs of nasal bone were reviewed for comparison. Results : Six patients had simple fracture, 10 patients had simple fracture with displacement, and 24 patients had comminuted fracture. Twenty-six patients had associated facialbone injuries which included fracture of nasal septum (n = 15), fracture of frontal process of maxilla (n = 9),fracture of ethmoid (n = 6), widening of nasofrontal suture (n = 5), and fracture of nasolacrimal duct (n = 2). In15 of 40 patients, CT could identify nasal bone fractures not detected on simple radiographs. Conclusion : Thin-section CT is a valuable aid in the evaluation of nasal bone fracture for accurate identification, nature, and combined facial injury.