We demonstrate a 1×2 optical switch matrix based on a liquid-actuated mirror reflector. Three indium tin oxide (ITO) electrodes are fabricated on the bottom substrate. One droplet is placed in the middle of the liquid channel and surrounded by density-matched silicone oil. A mirror reflector is placed on the droplet. In its initial state, the light beam can pass through the device from the light hole. When we apply voltage to one side of the ITO electrode, the droplet carries the mirror reflector, stretching and moving toward this side of the substrate. Therefore, the light beam is reflected by the mirror reflector. The light beam can pass through the device again when the mirror reflector is carried away by the droplet. Out-1 and Out-2 alternately change the switch-on and off states. Therefore, the device can achieve the function of a 1×2 optical switch matrix. Because it uses a mirror reflector to block the light beam, the device can attain 100% intensity attenuation. Our experiments show that the switch time from Out-1 (Out-2) to Out-2 (Out-1) are 129 and 123 ms, respectively. The proposed optical switch has potential applications in variable optical attenuators, electronic displays, and light shutters.