<p>A rubber composition for a tire tread preventing separation of the tread portion from the tire main body, and superior in grip performance and abrasion resistance. The tire tread portion includes a two-layered tread portion having cap rubber at the ground-contact surface side and base rubber at the inner side. The cap rubber has the JIS (K6253) type A hardness of 27 to 43 at 100°C. The base rubber has a thickness (TB) of at least 0.4 mm, and a loss tangent (tan ´) of at least 0.2. The ratio (TC/TB) of the thickness of the cap rubber (TC) to the thickness of the base rubber (TB) is at least 0.45.</p>
