The base isolation system allowing for the high efficiency energy absorption and the long-period structure with the combinations of elastic isolator and plastic damper is highlighted. Although many related studies are being conducted in S. Korea, fragmentary recognition that decrease in shear force by 2/3 reduction of acceleration as upper-structure is elastic is dominant. But verification of the plastic behavior of upper-structure is necessary in the case of unexpected severe earthquakes. In this study, the design based on energy balance method is conducted and the structural dynamic behavior such as the story damage distribution characteristics is analyzed by response analysis.