To provide: a rubber composition for a tire that can improve high mileage, mechanical strength and a filler gel fraction by excellent balance; and a pneumatic tire using the rubber composition.

A rubber composition for a tire includes: 20-80 pts.mass of silica and 2-20 pts.mass of carbon black, based on 100 pts.mass of a rubber component including 80-100 mass% of an epoxidized natural rubber in which an epoxidation rate is 2-8% by mole based on 100% by mole of the rubber component; and 4-12 pts.mass of a silane coupling agent based on 100 pts.mass of the silica.