In an optical switch for routing an optical signal, a deflecting member is mounted movably on a base and is tiltable about a fulcrum shaft so as to deflect the optical signal. Multiple elongate cantilevers are disposed on the base and are arranged around the deflecting member. Each cantilever has a coupling end portion connected to the base and opposite to a hammer end portion disposed on a periphery of the deflecting member. Control units are disposed on the base, and are operably and respectively associated with the cantilevers so as to control movement of the cantilevers to an appropriate one of a suspending position, where the hammer end portion is spaced apart from the deflecting member, and a pumping position, where the hammer end portion strikes the deflecting member, thereby forcing the deflecting member to tilt to a desired direction about the fulcrum shaft.