Negative electrode active material for non-aqueous electrolyte secondary battery, and non-aqueous electrolyte secondary battery

A negative electrode active material for a non-aqueous electrolyte secondary battery, the negative electrode active material comprising a silicate-containing composite (10) having a carbon phase (12) and a plurality of Si-containing silicate particles (14) dispersed in the carbon phase (12), the Si-containing silicate particles (14) having a silicate phase and a plurality of silicon particles dispersed in the silicate phase, the ratio (B/A) of the average particle diameter (B) of the silicate-containing composite (10) to the average particle diameter (A) of the Si-containing silicate particles (14) is from 15 to 120 (inclusive). 非水电解质二次电池用负极活性物质的特征在于，包含具有碳相(12)和分散于碳相(12)中的多个含有Si的硅酸盐粒子(14)的含有硅酸盐的复合体(10)，含有Si的硅酸盐粒子(14)具有硅酸盐相和分散于所述硅酸盐相中的多个硅粒子，相对于含有Si的硅酸盐粒子(14)的平均粒径(A)的、含有硅酸盐的复合体(10)的平均粒径(B)的比(B/A)为15以上且120以下。