An object of the present invention is to provide a rubber composition which is excellent in wet grip performance and abrasion resistance without deteriorating fuel efficiency, and a tire having a tread composed of the rubber composition. The present invention relates to a rubber composition comprising a rubber component comprising 20 to 90% by mass of a rubber component A and 10 to 80% by mass of a rubber component B, wherein an SP value of the rubber component A is not less than 17.8 (J/cm3)1/2 and an SP value of the rubber component B is lower than the SP value of the rubber component A by not less than 0.6 (J/cm3)1/2, and a tire having a tread composed of the rubber composition.