There are disclosed a frame assembly and liquid crystal display device for reducing leakage of light around a liquid crystal panel and improving display quality of the liquid crystal display device. The frame assembly includes a backboard in which a receiving portion is formed, a front frame mounted on the backboard around an periphery of the backboard and a buffer frame provided between the backboard and the front frame, wherein the backboard is provided with a first support portion, which is folded from a periphery of the backboard towards inside of the receiving portion so as to support the buffer frame. With the backboard of the above configuration, the support stability for the glue frame can be increased, and the deformation of the glue frame under a reaction force from the liquid crystal panel can be reduced, thereby reducing leakage of light around the liquid crystal panel and improving a display quality of the liquid crystal display device.