Purpose: This prospective, cross-sectional study evaluated the relationship between bone mineral density (BMD) and the width and height parameters of the mandibular residual ridge. Materials and Methods: BMD was determined in the lumbar spine and femoral necks by dual energy x-ray absorptiometry (DXA) in 45 edentulous, postmenopausal women (mean age, 72.08 ± 8.53 years) who had used conventional complete dentures for at least 3 years. Measurements of the mandibular residual ridge were performed using cone beam computed tomography (CBCT). Height and width measurements were performed in the midline and adjacent to the mental foramina. Data were analyzed with descriptive and analytic statistics. The relationship between BMD and mandibular height and width measurements was assessed using analysis of variance as well as linear and multivariate regression analyses. Eight patients were excluded from the study because they did not complete both of the required imaging analyses (DXA and/or CBCT). Results: There was no statistically significant relationship between BMD and mandibular bone height measurements in the midline and both regions of the mental foramina, and no statistically significant relationship existed between BMD and mandibular bone width measurements in the midline and both of the mental foramina regions. Conclusions: Postmenopausal women with reduced general BMD do not appear to have a reduction in the size of the mandibular residual ridge.