The present invention provides a rubber composition for a tire tread, in which processability, abrasion resistance, rolling resistance properties and wet grip performance are improved in a balanced manner. Specifically, the present invention provides a rubber composition for a tire tread comprising 5 to 150 parts by weight of silica having nitrogen-adsorbing specific surface area of 100 to 300 m.sup.2/g based on 100 parts of a rubber component containing 5 to 100% by weight of an epoxidized natural rubber, and 1 to 20 parts by weight of a silane coupling agent and 0.1 to 20 parts by weight of an anionic surfactant based on 100 parts by weight of the silica; and a rubber composition for a tire tread comprising 5 to 150 parts by weight of silica having nitrogen-adsorbing specific surface area of 100 to 300 m.sup.2/g and 1 to 10 parts by weight of a metal salt of stearic acid, based on 100 parts of a rubber component containing 5 to 100% by weight of an epoxidized natural rubber, and 1 to 20 parts by weight of a silane coupling agent based on 100 parts by weight of the silica.