An RF MEMS switch and a method for fabricating the same are disclosed, in which the RF MEMS device is down driven at a low voltage using a piezoelectric effect. The RF MEMS switch includes a substrate provided with RF signal lines and a cavity, a cantilever positioned on the cavity, having one end fixed to the substrate, and a contact pad connecting the RF signal lines with the cantilever in contact with the RF signal lines when the cantilever is down driven.