In recent years, much of effort has been devoted in the field of optical switches, including electro-optics (EO), magnetooptics (MO), acousto-optics (AO), liquid crystal (LC), and microelectromechanical systems (MEMS). However, issues which involve switching speed, aperture size, and extinction ratio cannot be simultaneously settled by the present approaches. The paper proposes a novel optical switch based on tunable photonic metamaterial. By the controllable external electrical or magnetic field, the nano-structure is forced to vary its optical properties to be an optical switch. The theoretical studies suggest that the device could offer the merit features of ultra-fast speed, large aperture, and high extinction ratio. In the future, we will not only thoroughly model the proposed devices, but investigate kinds of possible fabrication process to implement the design. To be a next-generation optical switch, the tunable photonic metamaterial has large potential in several civilian applications, including mobile high-speed display, free-space optical communication, solar concentration, and the optical printing.