Abstract: The object of the present invention is to provide a rubber composition with excellent workability, which gives vulcanized products with high wet skid resistance, low rolling resistance and high abrasion resistance, and a tire with those excellent properties. The rubber composition comprising a diene-based rubber (a), silica (b) and a compatibilizer (c). Said compatibilizer (c) is at least one selected from among (I) Aminosilane compounds; (II) Epoxy group-containing compounds; and (III)(IV) Compounds which have an amino group or a polymerizable unsaturated bond, together with a hydroxyl group, an epoxy group, an ether bond, a carboxyl group, an ester bond or a polymerizable unsaturated bond in the molecule.