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.