Abstract: A rubber composition comprising rubber, novolak-type phenolic resin and carbon black is very rigid and is adapted to be used as a bead filler rubber of a tire. Tires using the rubber composition are excellent in the high speed performance, lateral rigidity, ride feeling and durability.

Abstract: A pneumatic tire having remarkably low rolling resistance and high wet skid resistance without deteriorating the wear resistance is obtained by using in at least the ground-contact area of its tread, a rubber composition consisting essentially of 100 parts by weight of a mixed elastomer and 40-80 parts by weight of carbon black, the mixed elastomer consisting of 10-60 parts by weight of a solution-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 5-30% by weight and a trans-1,4 content in butadiene unit of not more than 45% by weight; 10-50 parts by weight of an emulsion-polymerized styrene-butadiene copolymer rubber having a bonded styrene content of 30-50% by weight; and 0-80 parts by weight of at least one rubber having a glass transition temperature of not higher than -50.degree. C.