In this article, an outline of dual energy X-ray absorptiometry (DXA), quantitative ultrasound (QUS), and radiogram, and their characteristics, problems, and assessment of osteoporosis in the elderly were reviewed. It is well known that both DXA and QUS are available to risk assessment of fractures. However, because lumbar bone mineral density (BMD) is overestimated in the elderly complicated with fracture, deformity, and osteosclerotic change in the lumbar vertebra (e), some cases are unsuitable to measurement of BMD with lumbar DXA. To define vertebral fracture, visual semiquantitative and morphometric methods are used. In addition, differential diagnosis of osteoporotic vertebral fractures is necessary. Thus, to establish an exact diagnosis of osteoporosis in the elderly, it is important to understand some problems associated with the elderly.