This paper describes earthquake response prediction methods and rationalization of dynamic design of mid-story isolated buildings. At first expressions of earthquake responses of the isolation story and first story, which dominate the seismic performance, are shown. Then, by drafting nomograph of relationship between maximum responses, it is shown that earthquake responses and response reduction by dampers and structural damping can be evaluated without using time history analysis. The dynamic design of mid-story isolated buildings are rationalized on an equality with base isolated buildings by flowcharting earthquake response prediction.