A bistable liquid crystal light valve (LCLV) and an operating method thereof are provided. The bistable LCLV comprises: a first transparent substrate and a second transparent substrate oppositely arranged in parallel to each other to form a liquid crystal cell; a first electrode disposed on an inner side of the first transparent substrate; a second electrode being disposed on an inner side of the second transparent substrate and corresponding to the first electrode; and a liquid crystal layer filled into the liquid crystal cell between the first transparent substrate and the second transparent substrate and including nematic liquid crystals and gelators dispersed in the nematic liquid crystals. The liquid crystal layer includes a transparent-state area and a scattering-state area arranged in parallel to each other in the horizontal direction of the first transparent substrate.