A backlight unit includes a receiving member, a lamp socket disposed in the receiving, member, a lamp coupled to the lamp socket and an inverter unit coupled to the lamp socket to supply electric power to the lamp. The receiving member further includes a guide portion for guiding the inverter unit The lamp socket includes a body, a first connector formed in a first end of the body, and a second connector formed in a second end of the body, wherein the first connector connects to the lamp and the second connector connects to the inverter unit.