Several epidemiologic studies suggested that osteoporosis and osteoporotic fractures are not uncommon in South Korea. However, these previous cohort studies had limitations that may have influenced their results and the generalizability of the study conclusions, including small sample sizes, inclusion of only women, enrollment of participants from specific areas, and nonrandom selection of participants. Recently, epidemiologic studies using a nationwide claim register have been performed to overcome these limitations through collaboration between the Korean Society of Bone and Mineral Research and Health Insurance Review Assessments. Our review of the Korean Nationwide-database Osteoporosis Study could be helpful to obtain accurate incidence and prevalence estimations of osteoporosis and osteoporosis-related fractures in Korea.