The authors proposed a damping device called switched mass damper.In the switched mass damper,a light mass ma is attached to the mass m of the primary system through a spring and a dashpot,and another mass mb is connected to or disconnected from the light mass ma using a friction clutch depending on the displacement of the light mass ma. In the previous reports,the authors showed that the switched mass damper has good damping performance for the mass switching pattern in which mb is disconnected when the displacement of ma becomes smaller than a given threshold and mb is connected when the displacement of ma becomes larger than the threshold. With further investigation, it has been found that reversing the mass switching pattern has possibility to increase the damping performance. In this report, first, damping performance for the reversed mass switching pattern is studied in detail through numerical simulation by examining the effect of each parameter of the switched mass damper on damping performance. Then, the result is confirmed by experiment.