A cross-linked rubber obtained by crosslinking a rubber composition containing a conjugated diene rubber and an inorganic filler, wherein when a loss tangent value of a non-interface component forming, of the cross-linked rubber ingredient, a portion other than an interface with the inorganic filler is represented as L(m) and a loss tangent value of an interface component forming, of the cross-linked rubber ingredient, an interface portion with the inorganic filler is represented as L(i), each loss tangent value being measured using an atomic force microscope in a state in which sinusoidal vibrations of 5 kHz are applied to the cross-linked rubber, the cross-linked rubber has a ratio L(i)/L(m) of 0.85 or less.