Positive Electrode Active Material for Secondary Battery, Preparation Method Thereof, and Positive Electrode for Secondary Battery Including Same

The present disclosure relates to a positive electrode active material for a secondary battery, the positive electrode active material being a lithium composite transition metal oxide particle including nickel (Ni) and cobalt (Co) and including at least one of manganese (Mn) and aluminum (Al), wherein the lithium composite transition metal oxide particle includes 60 mol % or greater of the nickel (Ni) in all metals excluding lithium, a doping element is doped on the lithium composite transition metal oxide particle, and the particle intensity of the lithium composite transition metal oxide particle is 210 MPa to 290 MPa.