Positive electrode active material for nonaqueous electrolyte secondary batteries, method for producing same, positive electrode for nonaqueous electrolyte secondary batteries using said positive electrode active material, and nonaqueous electrolyte secondary battery using said positive electrode

One embodiment of the positive electrode active material for nonaqueous electrolyte secondary batteries according to the present invention contains a lithium transition metal composite oxide that has a surface to which a compound containing a rare earth metal and silicic acid and/or boric acid adheres. One embodiment of the positive electrode according to the present invention comprises a positive electrode collector and a positive electrode mixture layer that is formed on at least one surface of the positive electrode collector. The positive electrode mixture layer contains: a positive electrode active material that contains a lithium transition metal composite oxide having a surface to which a compound containing a rare earth metal and silicic acid and/or boric acid adheres; a binder; and a conductive agent.