To provide a rubber composition for a tire tread that imparts largely enhanced braking properties of the tire and reduced rolling resistance to the tire tread.

A rubber composition comprises a blend rubber comprising 95-60 pts.wt. at least one kind of a diene rubber selected from the group consisting of a styrene-butadiene copolymer rubber (SBR), a polybutadiene rubber (BR), a polyisoprene rubber (IR) and natural rubber (NR) and having an average glass transition temperature Tg of -60°C to -30°C and 5-40 pts.wt. polynorbornene rubber, a carbon black having a specific surface area (N2 SA) of 85-200 m2/g as measured by nitrogen adsorption and a wet silica, wherein the carbon black and the wet silica are blended in total in an amount of 60-90 pts.wt. per 100 pts.wt. blend rubber and the wet silica is blended in an amount of 10-40 pts.wt. per 100 pts.wt. blend rubber.