To obtain a modified rubber having excellent temperature dependence or strain dependence of especially resistance to compression set (c-set) or viscoelasticity, a modified rubber composition made of the modified rubber as a raw material rubber and comprising silica compounded therein, and a rubber vibration insulator and a footwear using the modified rubber composition.

The modified rubber is obtained by copolymerizing a vinyl aromatic hydrocarbon with a conjugated diene using an organolithium as an initiator according to a solution polymerization method and modifying the resultant copolymer with a compound having ≥2 epoxy groups in the molecule.