This paper proposes a transflective liquid crystal display (LCD) in a whole-pixel switchable configuration with a high aperture ratio using an electrophoretic particle layer (EPL). The switchable transflective LCD consisted of the liquid crystal layer as a display unit, and the EPL as a switchable mirror. The switching of the EPL between the mirror for the reflective mode and the transparency for the transmissive mode was performed by controlling electrophoretic nanoparticles with an applied voltage in a three-electrode structure. The single pixel was used as the whole transmissive or reflective mode that corresponded to the switchable EPL mirror. Thus, a transflective LCD with a high aperture ratio was obtained.