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

A method for preparing a positive electrode active material for a secondary battery is provided. The method includes preparing a lithium composite transition metal oxide including nickel, cobalt, and manganese, wherein the content of the nickel in the total content of the transition metal is 60 mol % or greater. The lithium composite transition metal oxide, MgFas a fluorine (F) coating source, and a boron (B) coating source undergoes dry mixing and heat treatment to form a coating portion on the particle surface of the lithium composite transition metal oxide. In addition, a positive electrode active material prepared as described above, is also provided.