The reduction of occlusal force results in a decrease in bone density around the teeth, while an increase in occlusal force results in an increase in bone density. The density of the bone around the tooth can also affect the tooth movement. The purpose of this study was to evaluate right and left difference on bone density of alveolar bone in subjects with unilateral mastication habit. The cone-beam CT scans were obtained from 25 adult individuals who had unilateral mastication habit. Bone density was measured in Hounsfield unit at the middle between central and lateral incisors, canine and first premolar, first and second premolars, and first and second molars.Through the comparison of bone density between chewing and opposite side, the following results were obtained. 1. In the comparison of bone density according to the measurement area, it showed an increasing pattern from posteriors to anteriors. 2. In the comparison of bone density between the chewing and opposite side, chewing side had higher values with statistical significance. 3. The difference in bone density between the chewing and opposite side was more distinct in posteriors than in anteriors. The results indicate that the difference in alveolar bone density between chewing and opposite side should be taken into consideration when establishing treatment plan in unilateral mastication individuals.