A rubber composition having a high hysteresis loss is provided without impairment of other physical properties, such as fracture characteristics. The rubber composition includes 100 parts by weight of a rubber component, 0.1 to 100 parts by weight of graphitized carbon material, and a lipid the amount of which is 0.02 to 0.2 times the amount of the graphitized carbon material. Preferably, the graphitized carbon material is carbon fiber grown from a vapor phase or graphitized carbon black, and the lipid is a fatty acid. Preferably, the rubber composition according to the present invention has a loss tangent tan δ in the range of 0.05 to 0.5 at a temperature of 60 degree C. after vulcanization.