A liquid crystal display device includes a liquid crystal panel; a light guide plate disposed under the liquid crystal panel; a light emitting diode (LED) assembly disposed at a side of the light guide plate and including an LED and a printed circuit board (PCB), the LED arranged on the PCB to face the light guide plate; an LED heat sink surrounding the LED assembly and including a first portion, where the PCB is attached, and a second portion covering a bottom surface of the PCB; a bottom frame disposed under the light guide plate and including a bottom portion and a side portion, the bottom portion contacting the second portion of the LED heat sink, the bottom frame formed of an electrolytic galvanized iron (EGI); a top frame surrounding edges of the liquid crystal panel; and a main frame surrounding sides of the liquid crystal panel and combining with the top and bottom frames.