This invention provides a sintered electrode for a cold cathode tube in a cylindrical form having a bottom part on one end and an opening part on the other end, characterized in that a lead-in wire is joined integrally to the bottom part and a requirement of d2/d1>1 is satisfied wherein d1 represents the density of the sintered electrode; and d2 represents the density of the lead-in wire. According to the sintered electrode for a cold cathode tube, the bonding strength between the sintered electrode and the lead-in wire is high, and the handleability is good. The main component of the sintered electrode is particularly preferably identical to the main component of the lead-in wire. Enhancing the density of the lead-in wire can contribute to a further improvement, for example, in reliability.