Background: There are only few reports describing the texture of the inferior turbinate bone in normal and pathologic conditions. In this study, different types of human inferior turbinate bones were classified and radiological features of each type were defined. Methods: The shape, structure and density of the inferior turbinate bones were evaluated using paranasal sinus computed tomography images of 283 patients. The cross-sectional areas of the bony part of the inferior turbinate were measured in bone windows. Results: Human inferior turbinate bones were classified into four groups on the basis of different shape and structure as: Type 1, lamellar; Type 11, compact; Type III, combined Ope (compact with spongious component); Type IV, bullous. The distribution was as follows: 352 (62.19%) lamellar, 50 (8.83%) compact, 162 (28.63%) combined, and 2(0.35%) bullous type. Conclusion: Inferior turbinate bone is not in a uniform shape and structure. These diversities should be taken into consideration in radiological and clinical evaluation. (C) 2004 Elsevier Ireland Ltd. All rights reserved.