Top-Down Construction Method has been considered as the steadiest and the most reasonable method of construction since 1984 when it was applied to LG Da-Dong building and its usage in the field construction has since grown rapidly. With increased cases, engineers not only pursue their studies of R & D continuously but also develop various technical methods based on Top-Down Construction in an era of rapid technological change to adopt them to the field construction. Top-Down Construction meets the needs of these challenging points, such as reduction and eliminates of temporary equipment for supporting permanent structures on the ground, improved method of construction, shortening construction periods, cost reduction, and allows for minimal environmental impact.