Abstract: A negative electrode material for a nonaqueous electrolyte rechargeable battery that can stably and efficiently realize a high-performance nonaqueous electrolyte rechargeable battery in which a high discharge capacity, high charge/discharge efficiency at an initial stage and during charge/discharge cycles, and excellent charge/discharge cycle properties are provided as well as electrode expansion in volume after charge/discharge cycles is suppressed. The negative electrode material for a nonaqueous electrolyte rechargeable battery in the form of particles having, at least on the surface thereof, a compound of the phase in which an element Z is present in Si in a non-equilibrium state.