The present disclosure relates to a positive electrode material which includes a first positive electrode active material, and a second positive electrode active material in the form of a single particle, wherein an amount of lithium impurities on a surface of the second positive electrode active material is 0.14 wt % or less based on a total weight of the second positive electrode active material, and at least one of nickel, cobalt, and manganese included in the second positive electrode active material has a concentration gradient gradually changing from the center of the particle to a surface thereof, a method of preparing the positive electrode material, and a positive electrode for a lithium secondary battery and a lithium secondary battery which include the positive electrode material.