The Purpose of this study was evaluate the scoliosis prevalence in middle school students in Korea, and correlate those data with past references and other countries general prevalence. For the purpose, the methods of this study was administered by random survey of 46,428 middle school students in Seoul city was carried out to determine the prevalence of adolescent idiopathic scoliosis. There were 24,892 boys and 21,536 girls. Their age ranged from 12 to 15 years. Adams forward bending test and Scoliometer (Orthopaedic Systems, Inc, USA) were used to detect and measure the degree of rotation of trunk. Students more than 5 ATR were assessed subsequently by standardized clinical and radiological examinations. The result were as follows: 1. Using 10 degrees as cut-off points, 465 students were found to have structural idiopathic scoliosis, representing a prevalence of 0.9% overall. 2. The prevalence of the scoliosis has not changed from previously estimated rates in Korea, which was about 30 years ago. It nearly approximates with the prevalence of the world wide reported.