A liquid crystal display device has first and second liquid crystal panels (101, 102) mainly comprising liquid crystal cells (107, 108), respectively, disposed back to back to enable the visual recognition of the liquid crystal panels (101, 102). A light guide plate (112) is disposed between the first liquid crystal panel (101) and the second liquid crystal panel (102) with a light source (114) located adjacent to its one end face (112c), and a polarization separator (110) located between the first liquid crystal panel (101) and the light guide plate (112). Light emitted from the light guide plate (112) is split into two beams of polarized light: one is emitted to the first liquid crystal panel (101), and the other to the second liquid crystal panel (102) through the light guide plate (112). This constitution thins down a both-sided display liquid crystal display device and reduces power consumption.