A rubber composition for a bead filler contains a diene rubber, a carbon black and a nitrone compound having a carboxy group; the diene rubber contains a natural rubber and a styrene-butadiene rubber, wherein the content of the natural rubber in a total of the diene rubber and the nitrone compound is not less than 60 mass %, and the content of the styrene-butadiene rubber in a total of the diene rubber and the nitrone compound is not greater than 40 mass %; the content of the carbon black is 40 to 80 parts by mass per 100 parts by mass of a total of the diene rubber and the nitrone compound; and the content of the nitrone compound is 0.1 to 10 parts by mass per 100 parts by mass of a total of the diene rubber and the nitrone compound. Such rubber composition exhibits low heat build-up after vulcanization.