A liquid crystal device and the backlight module thereof are disclosed. The backlight module includes a back plate, at least one optical film, a plurality of optical fibers, and a reflector. The optical fibers are arranged to configure at least one light bar of the backlight module. The optical film and the back plate are spaced apart and opposite to each other to define a chamber for the light beams to be transmitted. The optical fibers positioned by the reflector are located at one lateral side of the chamber such that each of the optical fibers and the back plate form a predetermined inclined angle. In addition, the reflector is arranged at light-emitting locations of the optical fibers so as to adjust an emitting angle of the light beams entering the chamber. The back plate reflects the light beams irradiated on the back plate back to the optical film. The uniformity of the transmitted and mixed light beams is guaranteed when the backlight module is adopted in large-scale LCD.