Objective: The aim of this study was to measure and evaluate the bone anatomy morphology in mental foramen area using cone-beam computed tomography (CBCT). Methods: CBCT images of 100 patients were retrospective studied and measured. The anatomy morphology and adjacency of mental foramen, mental canal and mandibular canal were observed and measured. All the dates were analyzed by statistical package of SPSS17.0 software. Results: The anterior terminal part of the mandibular canal divided into mental canal and incisor nerve canal, 87.5% mental canal bended backward, upward and outward then opened to the mental foramen. The average distance from the superior border of mental foramen to the alveolar crest was (12.9±1.28) mm, and from the anterior border of mental foramen to the anterior end of mandibular canal was (3.6±1.14) mm, and from the inferior border of mental foramen to the superior border of mandibular canal was (3.9±0.97) mm, and from the superior border of mental foramen to the superior border of mental canal was (1.4±0.42) mm. Conclusions: CBCT can reflect the bone anatomy morphology of mandible accurately, and the safe distance from the tip of implant to the mental foramen should be re-evaluated.