Provided is a rubber composition having an intramolecular double bond capable of sulfur cross-linking, comprising at least one of 1 to 100 parts by mass of carbon black and 10 to 150 parts by mass of an inorganic filler other than carbon black, 0.1 to 50 parts by mass of a sulfur-containing compounding agent and 0.1 to 30 parts by mass of a hydrocarbon compound with both terminal groups thioesterified, per 100 parts by mass of the rubber having an intramolecular double bond capable of sulfur cross-linking. This rubber composition can provide a vulcanized substance having excellent toughness, for example, as a part of at least one of a cap tread, a side wall, a belt, an inner liner, a carcass and a bead of a pneumatic tire without substantially reducing processability of an unvulcanized substance and vulcanizate physical properties of the vulcanized substance.