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[Problem] To provide, for a short-arc type discharge lamp wherein a light rare earth oxide as an emitter substance is contained in a cathode in a luminous tube, a structure in which the light rare earth oxide as an emitter substance can be prevented from evaporating excessively from the cathode and thus resulting in early exhaustion. [Solution] A cathode (3) includes a body part (31) and a tip part (32) bonded to the tip side thereof and is characterized in that : the body part (31) comprises tungsten which contains a light rare earth oxide as an emitter substance; and the tip part (32) comprises tungsten which does not contain any emitter substance.