A highly durable cathode component for a discharge lamp is provided. A cathode component for a discharge lamp includes a barrel having a wire diameter of 2 to 35 mm and a tapered front end, wherein the cathode component comprises a tungsten alloy containing 0.5 to 3% by weight, in terms of oxide (ThO2), of a thorium component, not less than 90% of tungsten crystals are accounted for by tungsten crystals having a grain size in the range of 1 to 80 μm, as observed in terms of an area ratio of 300 μm×300 μm in unit area in a circumferential cross section of the barrel, and are accounted for by tungsten crystals having a grain size in the range of 10 to 120 μm, as observed in terms of an area ratio of 300 μm×300 μm in unit area in a side cross section of the barrel.