Abstract: A novel MEMS optical switch was designed and fabricated,which performs switching function by rotating vertical micro mirror.The use of curve shape electrode reduces the pull-in voltage of canti-lever drivereffectively.The combi nations of deepreactive ion etching technology and anisotropic etching of(110) silicon wafer make switch chips with aligning accessories.The device was tested to get electricand optical performances.The resul ts show that the driver's pull-in voltage is 78.5V,resonance fre-quency is 2.3kHz,the device's optical insertion loss is 5dB and crosstalk is 45dB.