The nonaqueous electrolyte secondary battery

A positive electrode active material for nonaqueous electrolyte secondary batteries is provided with which increased DCR after cycling can be controlled. A positive electrode active material according to an aspect of the present invention is secondary particles of a lithium transition metal oxide formed through the aggregation of primary particles of the oxide, the lithium transition metal oxide containing at least Ni. Secondary particles of a rare earth compound formed through the aggregation of particles of the rare earth compound are adhering to depressions each created between adjacent two of the primary particles on the surfaces of the secondary particles. The secondary particles of the rare earth compound are adhering to both of the two adjacent primary particles at the depressions.