There are provided (1) a sintered 
electrode for a 
cold cathode tube, comprising a cylindrical side wall part, a bottom part provided at one end of the side wall part, and an opening provided at another end of the side wall part, characterized in that the 
surface roughness (Sm) of the inner surface of the 
electrode is not more than 100 μm, (2) a 
cold cathode tube characterized by comprising: a hollow tubular light transparent 
bulb into which a 
discharge medium has been sealed; a fluorescent material layer provided on the inner wall surface of the tubular light transparent 
bulb; and a pair of the above sintered electrodes for a 
cold cathode tube provided respectively on both ends of the tubular light transparent 
bulb, and (3) a 
liquid crystal display device characterized by comprising: the above cold 
cathode tube; a 
light guide body disposed closely to the cold 
cathode tube; a reflector disposed on one surface side of the 
light guide body; and a 
liquid crystal display panel disposed on another surface side of the 
light guide body.According to the present invention, a cold 
cathode tube, which is low in 
operating voltage, can significantly suppress mercury consumption and has a prolonged service life, can be provided at low cost.