The present invention discloses a backlight module and a ventilation component thereof, and a back plate of the backlight module is provided with a plurality of the ventilation components. The ventilation component comprises: a tubular body, a ventilating filter, a filter washer, and a fixing ring. The tubular body is hollow, and the ventilating filter is carried in the tubular body. The ventilating filter can communicate the internal air with the external air of the backlight module circulate to effectively descend the temperature of the internal air, so that the thermal expansion of the light guide plate in the backlight module can be decreased to prevent from generating an optical problem.