A light source portion for a liquid crystal display (LCD) device may prevent reduction of the life span of the multiple lamps (LPs) when a surrounding temperature of the multiple LPs is less than a predetermined temperature of the LCD device. The LCD device comprises first and second brightness control portions receiving a brightness control signal, a temperature sensor, a signal output portion connected to the first and second brightness control portions and the temperature sensor, and an inverter portion turning on or turning off the multiple LPs based on the control signal from the signal output portion. When the temperature sensed by the temperature sensor is less than the predetermined temperature of the LCD device, the signal output portion switches the brightness control signal from a high level to a low level, and makes the multiple LPs maintain the high level until the surrounding temperature becomes more than the predetermined temperature.