A rubber composition for tires contains a diene rubber, silica, a sulfur-containing silane coupling agent and a triethoxysilane containing an alkyl group having a prescribed number of carbon atoms, wherein 50 mass % or more of the aforementioned diene rubber is a styrene-butadiene copolymer rubber, the aforementioned sulfur-containing silane coupling agent has a mercapto group, the content of the aforementioned silica is from 5 to 150 parts by mass per 100 parts by mass of the aforementioned diene rubber, the content of the aforementioned sulfur-containing silane coupling agent is from 3 to 15 mass % relative to the content of the aforementioned silica, and the content of the aforementioned alkyltriethoxysilane is from 0.1 to 20 mass % relative to the content of the aforementioned silica.