Dual energy X-ray absorptiometry (DXA) has become the most common method for measuring bone mineral density (BMD) of small animals in metabolic bone disease research, and errors should be minimized in all procedures involved in research studies in order to increase the accuracy of the study results. DXA is simpler and rapid compared to micro-computed tomography for quantitative analysis of change in trabecular bone of test subject. In human research, measuring BMD is widely used; postoperative evaluation on orthopedic surgery, evaluation of osteoporosis medication in menopause and many other areas of study. For the study, the inspector should be trained by the equipment manufacturer regarding the utilization and analysis of the equipment and regular phantom testing should be conducted to ensure the stability of the equipment, and precision tests should be conducted to analyze the positioning and data analysis. They should also be familiar with the clinical trials and conduct studies based on the approval of the Institutional Review Board. In the absolute BMD measurement of the human body, it is necessary to apply and compare the position and condition, rotation degree, region of interest, and area of the scan in the follow-up test. In the case of small animals, animal selection, measurement and equipment should be modeled to match the research. Therefore, we would like to provide information for researchers to minimize the errors, effective data management and accurate data presentation. This article reviews the process of DXA measurement for research purpose including plan for DXA examination, BMD measurement in a human body study and small animal studies.