To compare absorbed doses of cone-beam computed tomography (CBCT) according to field of view (FOV). Materials and Methods: To measure the absorbed doses of CBCT (Hitachi Medical Co.), we placed thermoluminescent dosimeter chips on both the submandibular and parotid glands, esophagus, tongue, and thyroid gland in a dental head phantom (CIRS). We used three image acquisition modes with FOV of different size: panoramic mode (P mode), implant mode (I mode), and dental mode (D mode). Two different dental mode scans were performed. One scanned the right upper molar region (D1), whereas the other scanned the left lower molar region (D2). Results: Average absorbed doses was lowest in D mode (average of D1 and D2, 4272.1 μGy) (p<0.05). Although the averages of absorbed doses between D1 and D2 showed no significant difference (p>0.05), the absorbed doses of esophagus (D1 756.9 μGy, D2 2938.2 μGy) and thyroid gland (D1 344.6 μGy, D2 880.1 μGy) were significantly different between D1 and D2. Conclusion: Since the average of absorbed doses was lowest with the smallest FOV, we must try to select the lowest FOV as possible when performing computed tomography, followed by careful diagnosis.