RF MEMS switches have the advantages of simple fabrication process and easy integration. However, the electrostatic drift and frequent mechanical collisions caused by the charge accumulation of dielectric film currently result in serious reliability problems that hinder the stability improvement of its embedded terminal RF system. Therefore, the structure of the dielectric suspension film is used to improve the charge accumulation problem, and the switch mechanical structure limit to realize the dynamic buffer of the switch to reduce the high-frequency mechanical collision damage. At the same time relying on the tab contact structure to reduce electrostatic drift. The theoretical models of dielectric film charging and switch life are established and the switch life is predicted. The results show that the designed switch life exceeds 12 900 hours. Compared with the existing RF MEMS switches, the proposed switch structure improves the lifetimes by 253 and 166 times, respectively, and greatly improves the electrostatic drift problem when the bipolar plate spacing and the metal beam-dielectric film spacing are equal, respectively. The isolation of -41. 31 dB, loss of -0. 25 dB, and response time of 50 μs at 52. 2 GHz operating frequency provide a theoretical model for high-performance, high-reliability, and long-life RF switches.