METHOD FOR PRODUCING RUBBER COMPOSITION, FUMED SILICA FOR RUBBER COMPOSITION, AND RUBBER COMPOSITION

[Problem] To provide: simple manufacturing of a rubber composition including fumed silica with a mixer-type kneading device that is typically used industrially; a rubber composition including fumed silica; and the fumed silica included therein. [Solution] A method for producing a rubber composition comprising: a step for subjecting fumed silica having a BET specific surface area of not less than 200 m2/g to a compression process so as to obtain compressed fumed silica having a tap density of not less than 200 g/L; and a step for kneading the compressed fumed silica with diene rubber. Fumed silica for a rubber composition, having a tap density of not less than 200 g/L, having a BET specific surface area of not less than 200 m2/g, and having been subjected to a surface treatment with a mercapto-thiocarboxylate oligomer. A rubber composition obtained by mixing compressed fumed silica which has a tap density of not less than 200 g/L and which has a BET specific surface area of not less than 200m2/g, natural rubber, and a mercapto-thiocarboxylate oligomer.