The present invention provides a backlight module, which at least comprises: a liquid crystal panel and a backlight sheet. The back of the liquid crystal panel is provided with multiple fastening devices which are provided with a holding portion thereon. The backlight sheet is provided with an assembling portion corresponding to the holding portion thereon. The fastening devices fix the liquid crystal panel on the backlight sheet by latching the assembling portion to the holding portion. The present invention also discloses a liquid crystal display device comprising the backlight module structure mentioned above. The backlight module and the liquid crystal display device according to the present invention can realize the backlight module without frame or with narrow frame structure and improve the assembling efficiency.