A quadrode field emission display is provided, where a low driving voltage is reached by an edge structure, and display in the dark is achieved by adding a sub-gate electrode. With respect to the electrical characteristics that an edge structure may raise the electric field intensity, an edge of a cathode plate through an opening of a gate layer is exposed, thereby forming the edge structure at an emitter to raise the electric field. It also reduces the driving voltage substantially. Therefore, the display in the dark is achieved by adjusting the voltage without changing the structure.