Compression fracture of thoracolumbar junction is considered to be stable, and usually treated by conservative methods, such as bed rest followed by bracing. However, we can often see the progression of deformity during follow-up. Authors had treated 62 cases with compression fractures of thoracolumbar junction conservatively at Ewha Woman' University Mokdong Hospital from September, 1993 to December, 1997, and analyzed risk factors of progression in anterior vertebral height (AVH) collapse and kyphotic angle after the minimum 1 year follow-up. The results were as follows; The anterior vertebral height significantly more decreased in the group with age over 60, but increase of kyphotic angle was not related with age factor. In female, decrease of AVH and increase of kyphotic angle were more than in male. AVH significantly more decreased in L1 than in T12 or L2, but increase of kyphotic angle was not related with fracture level. Decrease of AVH and increase of kyphotic angle were not related with fracture type. Osteoporosis seems to be the most important single risk factor in progression of compression and more strict wearing of well-fitting brace is necessary to protect the progression in case of severe osteoporosis.