A liquid crystal display device includes a liquid crystal display element, a frame member having a frame-shaped part which is arranged at a displaying surface side of the liquid crystal display element and having a display window exposing a displaying surface of the liquid crystal display element, and a side wall which is extended from the frame-shaped part along a thickness direction of the liquid crystal display element. A light source is arranged opposite to another surface of the liquid crystal display element which is opposite to the displaying surface thereof and irradiates the another surface of the liquid crystal display element with illumination light. A housing member which houses the light source has a main surface opposite to a frame-shaped part of the frame member and a side wall formed at a periphery of the main surface thereof.